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The design of atomic-scale microstructural traps to limit the diffusion of hydrogen is one key strategy in the development of hydrogen-embrittlement-resistant materials. In the case of bearing steels, an effective trapping mechanism may be the incorporation of finely dispersed V-Mo-Nb carbides in a ferrite matrix. First, we charged a ferritic steel with deuterium by means of electrolytic loading to achieve a high hydrogen concentration. We then immobilized it in the microstructure with a cryogenic transfer protocol before atom probe tomography (APT) analysis. Using APT, we show trapping of hydrogen within the core of these carbides with quantitative composition profiles. Furthermore, with this method the experiment can be feasibly replicated in any APT-equipped laboratory by using a simple cold chain.

Hydrogen embrittlement is a complex phenomenon, involving several length- and timescales, that affects a large class of metals. It can significantly reduce the ductility and load-bearing capacity and cause cracking and catastrophic brittle failures at stresses below the yield stress of susceptible materials. Despite a large research effort in attempting to understand the mechanisms of failure and in developing potential mitigating solutions, hydrogen embrittlement mechanisms are still not completely understood. There are controversial opinions in the literature regarding the underlying mechanisms and related experimental evidence supporting each of these theories. The aim of this paper is to provide a detailed review up to the current state of the art on the effect of hydrogen on the degradation of metals, with a particular focus on steels. Here, we describe the effect of hydrogen in steels from the atomistic to the continuum scale by reporting theoretical evidence supported by quantum calculation and modern experimental characterisation methods, macroscopic effects that influence the mechanical properties of steels and established damaging mechanisms for the embrittlement of steels. Furthermore, we give an insight into current approaches and new mitigation strategies used to design new steels resistant to hydrogen embrittlement.

Rewilding is increasingly recognized as a conservation tool but is often context specific, which inhibits broad application. Rewilding in Australia seeks to enhance ecosystem function and promote selfsustaining ecosystems. An absence of large-bodied native herbivores means trophic rewilding in mainland Australia has focused on the restoration of functions provided by apex predators and small mammals. Because of the pervasive influence of introduced mesopredators, predator-proof fences, and establishment of populations on predator-free islands are common rewilding approaches. This sets Australian rewilding apart from most jurisdictions and provides globally relevant insights but presents challenges to restoring function to broader landscapes. Passive rewilding is of limited utility in arid zones. Although increasing habitat extent and quality in mesic coastal areas may work, it will likely be necessary to undertake active management. Because much of Australia’s population is in urban areas, rewilding efforts must include urban areas to maximize effectiveness. Thus rewilding is not synonymous with wilderness and can occur over multiple scales. Rewilding efforts must recognize human effects on other species and benefit both nature and humans. Rewilding in Australia requires development of a shared vision and strategy and proof-of-concept projects to demonstrate the benefits. The repackaging of existing conservation activities as rewilding may confuse and undermine the success of rewilding programs and should be avoided. As elsewhere, rewilding in Australia should be viewed as an important conservation tool. El proceso de resilvestrar es reconocido cada vez más como una herramienta de conservación, pero con frecuencia depende del contexto ambiental, lo que inhibe su aplicación generalizada. En Australia, el proceso de resilvestrar busca mejorar la función ambiental y promover los ecosistemas auto-sustentables. Una ausencia de herbívoros nativos corpulentos significa que el resilvestreo trófico en la isla principal de Australia se ha enfocado en la restauración de las funciones que proporcionan los superdepredadores y los mamíferos pequeños. Debido a la influencia generalizada de los mesodepredadores introducidos, los cercos contra depredadores y el establecimiento de poblaciones en islas libres de depredadores son estrategias comunes de resilvestreo. Esto coloca al resilvestreo australiano aparte del que ocurre en muchas jurisdicciones y proporciona información relevante a nivel mundial, pero presenta retos para la restauración de la función en paisajes más amplios. El resilvestreo pasivo es de utilidadlimitadaen las zonas áridas. Aunqueel aumento de la extensión del hábitat y la calidad en las áreas meso-costeras puede funcionar, probablemente sea necesario emprender un manejo activo. Ya que la mayoría de la población de Australia se encuentra en áreas urbanas, los esfuerzos de resilvestreo deben incluir a las áreas urbanas para maximizar su efectividad. Por lo tanto, el resilvestreo no es sinónimo de la naturaleza y puede ocurrir en múltiples escalas. Los esfuerzos de resilvestreo deben reconocer los efectos que los humanos tienen sobre otras especies y deben beneficiar a la naturaleza y a las personas. El resilvestreo en Australia requiere del desarrollo de una visión compartida y de proyectos con prueba de concepto para demostrar sus beneficios. La reinvención de las actividades de conservación existentes como resilvestreo podría confundiry debilitar el éxito de los programas de resilvestreo, por lo que debería evitarse. Como en todos lados, el proceso de resilvestrar en Australia debería verse como una herramienta importante de conservación. 野化正越来越多地被用于保护，但它通常是环境特异的，难以广泛应用。在澳大利亚，野化项目旨在加强 生态系统功能，促进生态系統的自我维持。由于澳洲大陆缺乏大型本土食草动物，因此考虑营养级联的野化项目 主要关注顶级捕食者和小型哺乳动物的功能恢复。受到引人的中等体型捕食者带来的普遍影响，野化中常常用 到布设防捕食者围栏和在没有捕食者的岛屿上建立种群的方法。这使澳大利亚的野化有别于大多数国家和地 区为全世界的野化项目提供了见解，{旦也对在更大尺度的景观上进行功能恢复提出了挑故。在干旱地区，被动 野化的效果有限。尽管在湿度适中沿海地区，扩大生境范围、提高生境质量可能有用，但也需要进行积极的管 理。由于澳大利亚大部分人口都生活在城市地区，要实现效益最大化，野化工作必须要包括城市地区。因此，野 化不等同于荒化，且可以在多个尺度上进行。另外，野化工作必须认识到人类对其它物种的影响，并使自然和人 类都能受益。澳大利亚的野化需要发展共同观念和概念验诬项目来展现其效益。而若将现有的保护活动重新包 装为野化，可能会混淆和破坏野化项目的成功，应注意避免。和其它地方一祥，澳大利亚也应该将野化作为ー种 重要的保护工具。

The first absolute experimental bond dissociation energies (BDEs) for the main heterolytic bond cleavages of four benzylpyridinium “thermometer” ions are measured using threshold collision-induced dissociation in a guided ion beam tandem mass spectrometer. In this experiment, substituted benzylpyridinium ions are introduced into the apparatus using an electrospray ionization source, thermalized, and collided with Xe at varied kinetic energies to determine absolute cross-sections for these reactions. Various effects are accounted for, including kinetic shifts, multiple collisions, and internal and kinetic energy distributions. These experimentally measured 0 K BDEs are compared with computationally predicted values at the B3LYP-GD3BJ, M06-GD3, and MP2(full) levels of theory with a 6-311+G(2d,2p) basis set using vibrational frequencies and geometries determined at the B3LYP/6-311+G(d,p) level. Additional dissociation pathways are observed for nitrobenzylpyridinium experimentally and investigated using these same levels of theory. Experimental BDEs are also compared against values in the literature at the AM1, HF, B3LYP, B3P86, and CCSD(T) levels of theory. Of the calculated values obtained in this work, the MP2(full) level of theory with counterpoise corrections best reproduces the experimental results, as do the similar literature CCSD(T) values. Lastly, the survival yield method is used to determine the characteristic temperature (T char ) of the electrospray source prior to the thermalization region and to confirm efficient thermalization. Graphical Abstract ᅟ

Introduction and Objectives: The frequency of copper deficiency and clinical manifestations following roux-en-y gastric bypass (RYGB) surgery is not yet clear. Objectives were to determine the prevalence and incidence of copper deficiency in patients who have undergone RYGB. Design and Methods: We sought to determine the number of RYGB patients undergoing medical and nutritional follow-up visits at the Emory Bariatric Center who experienced copper deficiency and associated hematological and neurological complaints ( n =136). Separately, in patients followed longitudinally before and during 6 and 24 months following RYGB surgery, we obtained measures of copper status ( n =16). Systemic blood cell counts and measures of copper, zinc and ceruloplasmin were determined using standardized assays in reference laboratories including atomic absorption spectrometry and immunoassays. Results: Thirteen patients were identified to have copper deficiency suggesting a prevalence of copper deficiency of 9.6%, and the majority of these had concomitant complications including anemia, leukopenia and various neuro-muscular abnormalities. In the longitudinal study, plasma copper concentrations and ceruloplasmin activity decreased over 6 and 24 months following surgery, respectively ( P <0.05), but plasma zinc concentrations did not change. A simultaneous decrease in white blood cells was observed ( P <0.05). The incidence of copper deficiency in these subjects was determined to be 18.8%. Conclusions: The prevalence and incidence of copper deficiency following RYGB surgery was determined to be 9.6% and 18.8%, respectively, with many patients experiencing mild-to-moderate symptoms. Given that copper deficiency can lead to serious and irreversible complications if untreated, frequent monitoring of the copper status of RYGB patients is warranted.

The Centers for Medicare and Medicaid Services identified unplanned hospital readmissions as a critical healthcare quality and cost problem. Improvements in hospital discharge decision-making and post-discharge care are needed to address the problem. Utilization of clinical decision support (CDS) can improve discharge decision-making but little is known about the empirical significance of two opposing problems that can occur: (1) negligible uptake of CDS by providers or (2) over-reliance on CDS and underuse of other information. This paper reports an experiment where, in addition to electronic medical records (EMR), clinical decision-makers are provided subjective reports by standardized patients, or CDS information, or both. Subjective information, reports of being eager or reluctant for discharge, was obtained during examinations of standardized patients, who are regularly employed in medical education, and in our experiment had been given scripts for the experimental treatments. The CDS tool presents discharge recommendations obtained from econometric analysis of data from de-identified EMR of hospital patients. 38 clinical decision-makers in the experiment, who were third and fourth year medical students, discharged eight simulated patient encounters with an average length of stay 8.1 in the CDS supported group and 8.8 days in the control group. When the recommendation was “Discharge,” CDS uptake of “Discharge” recommendation was 20% higher for eager than reluctant patients. Compared to discharge decisions in the absence of patient reports: (i) odds of discharging reluctant standardized patients were 67% lower in the CDS-assisted group and 40% lower in the control (no-CDS) group; whereas (ii) odds of discharging eager standardized patients were 75% higher in the control group and similar in CDS-assisted group. These findings indicate that participants were neither ignoring nor over-relying on CDS.

Aims: To describe the optics of in vivo confocal microscopy, its advantages over previous methods, and to summarise the literature that arose from its use for the observation of the human cornea. A critical review of the clinical usefulness of this new technology for the corneal examination is undertaken. Methods: Confocal microscopes obtain increased resolution by limiting the illumination and observation systems to a single point. Rapid scanning is used to reconstruct a full field of view and allows for “real time” viewing. Results: Coronal sections of the in situ epithelium, Bowman’s membrane, stroma, and endothelium can be visualised at a resolution of 1–2 μm. A backscattered light intensity curve allows objective measurements of sublayer thickness and corneal haze to be taken. In vivo confocal microscopy is therefore particularly useful in the areas of infective keratitis, corneal dystrophies, refractive surgery, and contact lens wear, where it aids in differential diagnosis and detection of subtle short and long term changes. Real time endothelial cell assessment can also be performed. Conclusion: Because of their ability to visualise living tissue at cellular levels, confocal microscopes have proved useful additions to the current clinical tools.

Background Three-dimensional cultures of mammary epithelial cells allow for biologically-relevant studies of the development of the mammary gland in rodents and humans under normal and pathological conditions, like carcinogenesis. Under these conditions, mammotropic hormones play significant roles in tissue morphogenesis. Therefore, a system that recreates the normal, hormonally responsive epithelium would be a valuable tool to study the normal state and its transition to carcinogenesis. MCF-12A cells have been claimed to be non-tumorigenic mammary epithelial cells with reported sensitivity to estrogens. In this study, we aimed at characterizing MCF-12A cells for use in a hormone-responsive 3D culture system to determine their usefulness as a tool to identify normal and abnormal microenvironmental cues. Methods MCF-12A cells were single-cell cloned in order to investigate their heterogeneous makeup. The parental cells were then treated with estradiol to investigate proliferative and transcriptional responses through the estrogen receptor alpha. Finally, parental cells and epithelial-like cell-derived clones were seeded in rat-tail collagen I to profile the morphogenesis of multicellular 3D structures. The resultant structures were then analyzed using unsupervised morphometric analysis. Results MCF-12A cells consist of epithelial-like colonies which shed elongated, freely growing cells on the colony’s edges. The cells express E-cadherin as well as mesenchymal vimentin but do not express markers associated with myoepithelial cells or fibroblasts. Treatment with estradiol does not affect either the proliferation rate or the induction of gene expression in MCF-12A cells. Parental MCF-12A cells form acini, solid spheres and elongated branching ducts when grown in rat-tail collagen type I matrix, the geometries and distribution of which are altered following the removal of fibroblast-like cells. Conclusions MCF-12A cells are a heterogeneous pseudo-epithelial cell line capable of forming a variety of multicellular structures in 3D culture. We found no indication that the cells display estrogen-responsive characteristics, thus refuting previous studies which reported estrogen responsiveness. We report that MCF-12A cells are not suited for use in studies in which differential behaviors of “normal” and “cancerous” estrogen-responsive cells are to be compared.

Background The objective of the study was to assess the risk factors associated with return to the operating room in bariatric surgery patients. Methods Using the American College of Surgeons-National Surgical Quality Improvement Project’s participant-use file, patients who underwent laparoscopic gastric bypass (LRYGB) and adjustable gastric band (LAGB) procedures for morbid obesity were identified. Several pre-, peri-, and postoperative variables, including 30 day morbidity and mortality, were collected. The study population was divided into two groups: patients returning to the operating room (group 1), and patients not returning to the operating room (group 2). Variables analyzed included postoperative complications, overall morbidity, and mortality. Relationships between preoperative and perioperative factors leading to the return to the operating room also were analyzed. Results Of 28,241 (LRYGB = 18,671, LAGB = 9,570) patients included in the study, 644 (2.3 %) patients returned to the operating room. Of the study population, 30 day mortality rate was 0.13 % (37/28,241) and morbidity was 4.1 % (1,155/28,241). Patients returning to the operating room had a higher mortality [14/644 (2.2 %) vs. 23/27,597 (0.01 %); P  < 0.001], and morbidity [258/644 (40 %) vs. 897/27,579 (3.3 %); P  < 0.001] compared with those who did not return to the operating room. Postoperative complications (superficial wound infection, deep surgical site infection, organ space infection, pneumonia, pulmonary embolism, renal insufficiency, renal failure, septic shock, and length of stay) were significantly higher for patients who required reoperation. On multivariate logistic regression analysis, the bypass operation, bleeding disorder, patients on dialysis, preoperative hematocrit, preoperative low albumin, and length of operation were associated with increased risk of return to the operating room. Summary In the bariatric population, return to the operating room is associated with significantly higher morbidity and mortality. Patients who are on dialysis, have a low preoperative serum albumin, and a history of bleeding disorders have a higher chance of return to the operating room. In addition, patients who have a long operation are at increased risk for return to the operating room. Increased awareness of these predictors will be helpful to counsel the patients before the operation.