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The Beam Energy Scan Theory (BEST) collaboration's equation of state (EoS) incorporates a 3D Ising model critical point into the Quantum Chromodynamics (QCD) equation of state from lattice simulations. However, it contains 4 free parameters related to the size and location of the critical region in the QCD phase diagram. Certain combinations of the free parameters lead to acausal or unstable realizations of the EoS that should not be considered. In this work, we use an active learning framework to rule out pathological EoS efficiently. We find that checking stability and causality for a small portion of the parameters' range is sufficient to construct algorithms that perform with $>$96% accuracy across the entire parameter space. Though in this work we focus on a specific case, our approach can be generalized to any EoS containing a parameter space-class correspondence., 14 pages, 9 figures

Hollow-walled lattices are novel cellular materials with lower densities than conventional dense-walled lattices. However, their manufacturability by laser powder bed fusion (LPBF) is not yet established. This study investigates the LPBF manufacturability of Ti-6Al-4V hollow-walled struts with respect to strut outer diameter, wall thickness (controlled by laser scan path), and inclination angle, while the strut length is purposely limited to 10–15 mm, typical of lattice unit dimensions. The manufacturability was reliable for outer diameters exceeding 0.5 mm and wall thicknesses exceeding 0.24 mm over the inclines of 22.5°–90°. To ensure a manufacturable hollow cylindrical channel by LPBF, we recommend a minimum inner diameter of 4Dv(90) according to the feedstock powder size distribution. The average inconsistency of 5.13% between the designed and manufactured outer diameters was substantially lower than that achievable by conventional manufacturing. The findings of this study provide necessary guidance for the future manufacture of hollow-walled lattices by LPBF.

Introduction Heller myotomy (HM) remains the gold standard procedure for achalasia. The addition of different types of fundoplication to HM has been debated in several studies. Given the contradictory reports, this meta-analysis was undertaken to compare different outcomes after HM and HM with fundoplication (HMF). Methods An electronic search was performed among five major databases (PubMed, Ovid, Scopus, Cochrane Library, Google Scholar) from inception to October 2019, identifying all randomised and non-randomised studies comparing HM with HMF. Two authors searched electronic databases using the keywords ‘achalasia’ AND ‘dysphagia’ AND ‘gastroesophageal reflux’ and all data were pooled for random-effects meta-analysis. The primary and secondary outcomes were gastroesophageal reflux and dysphagia, respectively. Results A total of six studies were included and involved 576 patients comparing HM and HMF. There was no statistically significant difference between gastroesophageal reflux in the HM vs HMF group (21.3% vs 22.9%, RR 1.32, 95% CI 0.60–2.88, p = 0.49). There was a slightly higher incidence of dysphagia observed in HM vs HMF (14.8% vs 10.8%, RR 1.54, 95% CI 0.98–2.41, p = 0.06). Conclusions There was no statistically significant difference in long-term outcomes between a group of patients undergoing HM and a group who underwent HM with fundoplication.

Aim To evaluate the care and outcomes for women with breast cancer over the age of 70 and to compare our performance at AUH against the national outcomes. Method Using the online database at AUH we gathered the following data: age, TNM status, surgical management, histology, adjuvant treatment (radiotherapy, chemotherapy, hormone therapy, targeted therapy) and reasons for alterations in planned therapy. Results We audited 176 patients between 2018 and 2019. Age varied between 70 and 95 years old. 10 patients suffered from DCIS, 152 from invasive breast cancer and 14 from de novo metastatic breast cancer. 40% of patients with DCIS with underwent WLE, 40% underwent mastectomy and 20% were not offered an operation as they were unfit. Invasive breast cancer accounted for the majority of cases. 86% were ER/PR positive and 12.2% were Her-2 positive. 35.7% underwent mastectomy, 64.4% underwent WLE and 0.8% VAB excision. 51.7% had Sentinel node biopsy, 15.3% underwent axillary clearance and 1.7 % had axillary sampling. 7.9% of patients presented with metastatic disease. 2.6% of those patients had palliative radiotherapy. Primary endocrine therapy was commenced on 21.1% of patients. Factors that lead to PET were that 47% of patients were unfit for an operation, 20.6% refused surgical intervention, 11.7% had concurrent aggressive malignancy and 8.8% were inoperable. Conclusions Overall, successful results were achieved for this group of patients compared to the national outcomes. 99.4% of patients in our centre had triple assessment prior to MDT. Further review of functional status and service outcomes will be required to be audited.

The rapid growth of additive manufacturing (AM) technologies has enabled the emergence of geometrically sophisticated materials or structures with tailored and/or enhanced mechanical responses. In addition to dense-walled lattice structures, innovation within the past decade has identified that hollow-walled lattice topologies exhibit the multifaceted potential of competitive strength and rigidity, whilst displaying unique deformation behaviours, indicating that they may be an important subsequent step in lattice evolution. Hollow-walled sections facilitate density and geometrical parameters well below what is achievable by dense-walled sections, providing additional hierarchies of architecture at micrometre to even nanoscale proportion. Their wall thickness can range from 20 nm to 800 µm while the relative density can span three orders of magnitude between 0.01% and 30%. Despite nearly a decade of research into hollow-walled lattice topologies, no meta-analysis exists to provide an informative overview of these structures. This research addresses this deficiency and provides a data-driven review of hollow-walled lattice materials. It elucidates how these hollow-walled lattices deviate from the current limitations of dense-walled lattices and the underlying mechanisms that dictate their performance, with data accumulated from an exhaustive collection of literature sources. A range of new insights into their design and manufacture is discussed for their future research and applications in different engineering fields.

Retinal dopamine is a critical modulator of high acuity, light-adapted vision and photoreceptor coupling in the retina. Dopaminergic amacrine cells (DACs) serve as the sole source of retinal dopamine, and dopamine release in the retina follows a circadian rhythm and is modulated by light exposure. However, the retinal circuits through which light influences the development and function of DACs are still unknown. Intrinsically photosensitive retinal ganglion cells (ipRGCs) have emerged as a prime target for influencing retinal dopamine levels because they costratify with DACs in the inner plexiform layer and signal to them in a retrograde manner. Surprisingly, using genetic mouse models lacking specific phototransduction pathways, we find that while light influences the total number of DACs and retinal dopamine levels, this effect does not require ipRGCs. Instead, we find that the rod pathway is a critical modulator of both DAC number and retinal dopamine levels.

An understanding of the role of religion and spirituality in the mental health of older adults is needed to better treat and work with such populations so that they can prepare themselves long in advance to respond to the challenges of old age. Research shows that the use of religion and spirituality in therapy with clients, who profess such beliefs, can have a positive impact in the therapeutic encounter. This article draws on disengagement, reengagement, and activity theory to show how religion and spirituality can be used in treating older adults. Older adults can age gracefully if they learn new ways to build community, find spiritual and cultural interests, and continue to work for as long as they can render service, even if limited.

Double elevator palsy (DEP) currently known as Monocular Elevation Deficit is a rare condition characterized by restricted elevation of one eye in all positions of up gaze. Clinically it presents as a unilateral restriction of superior rectus (SR) and inferior oblique (IO). We present a case report of DEP in 3 year old boy who presented with sudden onset of DEP in right eye in our OPD. Very little information on acquired causes of DEP is available. Diagnosis, differential diagnosis and management are discussed and then the literature is reviewed.

A dislocation simulation model has been proposed to predict the brittle–ductile transition in ferritic steels in Part I. Here we extend the model to address the problem of inherent scatter in fracture toughness measurements. We carried out a series of Monte Carlo simulations using distributions of microcracks situated on the plane of a main macrocrack. Detailed statistical analysis of the simulation results showed the following: (a) fracture is initiated at one of the microcracks whose size is at the tail of the size distribution function, and (b) the inherent scatter arises from the distribution in the size of the critical microcrack that initiates the fracture and not from the variation of the location of the critical microcrack. Utilizing the weakest-link theory, Weibull analysis shows good agreement with the Weibull modulus values obtained from fracture toughness measurements.

We present a model for the brittle-ductile transition in ferritic steels based on two dimensional discrete dislocation simulations of crack-tip plastic- ity. The sum of elastic fields of the crack and the emitted dislocations defines an elasto-plastic crack field. Effects of crack-tip blunting of the macrocrack are included in the simulations. The plastic zone characteristics are found to be in agreement with continuum models, with the added advantage that the hardening behavior comes out naturally in our model. The present model is composed of a macrocrack with microcracks ahead of it in its crack-plane. These microcracks represent potential fracture sites at internal inhomogeneities, such as brittle precipitates. Dislocations that are emitted from the crack-tip account for plasticity. When the tensile stress along the crack plane attains a critical value rF over a distance fracture is assumed to take place. The brittle-ductile transition curve is obtained by deter- mining the fracture toughness at various temperatures. Factors that contribute to the sharp upturn in fracture toughness with increasing temper- ature are found to be: the increase in dislocations mobility, and the decrease in tensile stress ahead of the macrocrack tip due to increase in blunting, and the slight increase in fracture stress of microcracks due to increase in plasticity at the microcrack. The model not only predicts the sharp increase in fracture toughness near the brittle-ductile transition temper- ature but also predicts the limiting temperature above which valid fracture toughness values cannot be estimated; which should correspond to the ductile regime. The obtained results are in reasonable agreement when compared with the existing exper- imental data.

We present here a computer simulation model for prediction of the shift in the brittle–ductile transition with irradiation dose. The model is based on discrete dislocation simulation, and is applied to the ferritic/martensitic steel, F82H. The simulated crack system involves microcracks embedded in the plastic zone of a macrocrack. The inherent scatter in fracture toughness measurements are studied by using a size distribution for microcracks, distributed on the crack plane of the macrocrack. The criterion for fracture is the propagation of any of these microcracks located at a distance ahead of the macrocrack. The fracture toughness of F82H at various temperatures is estimated by using measured irradiated and unirradiated yield stress values. Using the yield stress–temperature dependence; the shift in the transition temperature with the irradiation dose is simulated and compared with experiments. Furthermore, the observed scatter in fracture toughness measurements is found to be the result of the distribution in the size of microcracks.

Transportation of long turbine blades from one place to another is a difficult process. Hence a feasibility study of modularization of wind turbine blade was taken from structural standpoint through finite element analysis. Initially, a non-segmented blade is modeled and its structural behavior is evaluated to serve as reference. The resonant, static bending and fatigue tests are simulated in accordance with IEC61400-23 standard for comparison purpose. The non-segmented test blade is separated at suitable location based on trade off studies and the segments are joined with an innovative double strap bonded joint configuration. The adhesive joint is modeled by adopting cohesive zone modeling approach in ANSYS. The developed blade model is analyzed for its structural response through simulation. Performances of both the blades are found to be similar, which indicates that, efficient segmentation of the long blade is possible which facilitates easy transportation of the blades and on site reassembling. The location selected for segmentation and adopted joint configuration has resulted in an efficient segmented blade model which proves the methodology adopted for segmentation was quite effective. The developed segmented blade appears to be the viable alternative considering its structural response specifically in fatigue within considered assumptions., {"references":["\"Design limits and solutions for very large wind turbines,\" UPWIND,\nEWEA, pp. 10-18, March 2011.","D. A. Griffin, \"Blade System Design Studies Volume I: Composite\nTechnologies for Large Wind,\" SANDIA National Laboratories,\nCalifornia, USA, 2002.","F. A. Saldanha, V. V. Rao, J. Chirstopher and R. 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Working with dreams is useful with grief and loss clients who present with dreams. Adlerian dream analysis is one-way of exploring dreams. It incorporates the life-style of the client. This case report demonstrates how Adlerian dream analysis was used with a client. Progress was noted in improved life-style once the client began to talk about her dream.

Aim To investigate the characteristics of paediatric acquired brain injury (ABI) case managers and their organizations in Australia, and to determine the ways in which case managers deliver their service, maintain professional development and evaluate outcomes. Methods Postal survey of 57 known paediatric ABI case managers working at 24 separate organizations in Australia. Results Out of 40 questionnaires returned (70%), the majority of respondents had been providing case management for over 5 years (55%). Co-ordination of services was ranked the most important component of case management, with services most frequently delivered by telephone. Evaluation of case management outcomes was reported by only 52% of the case managers. Whilst the majority of case managers had received some form of training (83%), this varied widely from informal in-house training, to workshops run by insurance companies and government agencies. Discussion This survey provides information about current case management practices for children with ABI in Australia. Detailing what case managers do is a first step towards developing controlled research designs which are required to demonstrate whether case management is effective in terms of clinical outcomes and cost–benefit.

A recently introduced method of crack representation as a distribution of three-dimensional Volterra dislocations is used in conjunction with two-dimensional dislocation dynamics simulations to study the brittle to ductile transition behavior of Ferritic Steels. The crack-tip plasticity zone is represented as an array of discrete dislocations emitted from crack-tip sources. The dislocations shield the crack and result in an increase of the applied stress intensity for fracture from the pure Griffith value. The crack system responsible for fracture in Ferritic Steels is modeled by a macrocrack and a microcrack in its field. Crack-tip plasticity of microcrack is also modeled by arrays of emitted dislocations. The simulations are performed for different friction stresses corresponding to different yield stresses or temperatures. The brittle to ductile transition fracture toughness curve is obtained and compared to experiments.

We use a multiscale approach in which results from atomistic simulations are combined with discrete dislocation (DD) dynamics simulations of crack-tip plasticity. The method is used to study the effects of dislocation blocking on the fracture behavior of α-iron and aluminum. We studied the effects of blocking for distances ranging from 5 nm to 1 mm and find that the fracture resistance is increased with increasing blocking distance. The atomistic and dislocation dynamics simulations show that the blocking of dislocations causes a net decrease in the shear stress projected on the slip plane, preventing further dislocation emission. Semi-brittle cleavage occurs after a certain number of dislocations are emitted, explicitly demonstrating the embrittling effects of dislocation blocking. This effect can contribute to the brittle behavior observed in some nanocrystalline metals.

The initiation of the cleavage fracture of ferritic steels at cracked grain boundary carbides situated in a plastic zone is modelled, using a 2D discrete dislocation simulation of the plastic zones associated with a microcrack under triaxial loading. Fracture is assumed to occur when the local stress intensity factor for the microcrack equals KIC. For microcracks in the size range 0.1-10 μm, the applied stress at fracture, σF, is found to be independent of the yield stress (in the range 200-1600 MPa) and therefore of temperature. The dependence of σF on the crack size deviates from a Griffith type relation. These predictions are consistent with experimental data on steels in the literature. The values of σF predicted are in good agreement with the experimental values. The results suggest that only a small fraction of carbides are in configurations leading to fracture. © 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

We demonstrate the existence of a crossover in the dynamics of the PLC effect from chaotic to self-organized critical nature by analysing the stress–strain curves obtained from single crystals of Al–10%Cu subjected to three levels of constant strain rate deformation. At the lowest and intermediate strain rates, we provide an unambiguous support for the existence of a chaotic regime. For these two strain rates, the distributions of stress drops are peaked. At the highest strain rate, we find that the distributions of stress drops and their durations exhibit a power law behaviour reminiscent of a self-organized critical state. We also show that scaling relations are obeyed by the various exponents.

The association of HLA class I heavy chains with β2-microglobulin (β2m) changes their antigenic profile. As a result, Abs react with either β2m-free or β2m-associated HLA class I heavy chains. An exception to this rule is the mAb TP25.99, which reacts with both β2m-associated and β2m-free HLA class I heavy chains. The reactivity with β2m-associated HLA class I heavy chains is mediated by a conformational determinant expressed on all HLA-A, -B, and -C Ags. This determinant has been mapped to amino acid residues 194–198 in the α3 domain. The reactivity with β2m-free HLA class I heavy chains is mediated by a linear determinant expressed on all HLA-B Ags except the HLA-B73 allospecificity and on

Utilizing phage display peptide libraries, we have identified and mapped the antigenic determinants recognized by mouse monoclonal antibodies (mAb) on two sets of immunologically important molecules, HLA class I and class II antigens. Anti-HLA class I mAb TP25.99 recognizes a conformational and a linear determinant on distinct regions of the HLA class I α3 domain. Anti-HLA class I mAb HO-4 recognizes a conformational determinant on the α2 domain of HLA-A2 and A28 allospecificities. Anti-HLA-DR1, -DR4, -DR6, -DR8, -DR9 mAb SM/549 recognizes a conformational determinant on the β chain of HLA class II antigens. These results indicate the versatility of phage display peptide libraries to characterize antigenic determinants recognized by anti-HLA mAb.

INSPIRE is a Web-based system for the support and conduct of negotiations. The primary uses of the system are training and research. Between July 1996 and April 1997, 281 bilateral negotiations were conducted through the system by managers, engineers and students from over 50 countries. INSPIRE has been used at eight universities and training centers. In research it is being used to study cross-cultural differences in decision making and the use of computer support in negotiation. This paper outlines the system, the negotiation methodology embedded in it, and reports the initial results of the experimental study of the impact of culture on Web-based bilateral negotiation.

To broaden the specificity of the Abs recognizing human melanoma-associated Ags (MAAs), we have isolated human single-chain fragment of the V region (scFv) fragments by panning the synthetic phage Ab library (#1) with the human melanoma cell lines S5 and SK-MEL-28. All of the isolated scFv fragments reacted with the mouse mAb defined high molecular weight melanoma-associated Ag (HMW-MAA). scFv #70 immunoprecipitates the two characteristic subunits of HMW-MAA, while scFv #28 only immunoprecipitates its large subunit. These results challenge the current view regarding the structure of HMW-MAA and indicate that it consists of two independent subunits. The human scFv fragments share some similarities with the mouse anti-HMW-MAA mAb. Like mAb 149.53 and 225.28, scFv #28 reacts with rat B49 neural cells that express a homologue of HMW-MAA. scFv #70 reacts with a determinant that is spatially close to the one identified by mAbs 149.53, VT68.2, and VT86. Besides suggesting similarities in the recognition of human melanoma cells by the mouse and human Ab repertoire, these results indicate that the Abs isolated from synthetic Ab libraries resemble those that are found in natural Ab repertoires. The restricted diversity of the scFv fragments that were isolated by panning synthetic Ab libraries with different melanoma cell lines suggests that certain Ags, like HMW-MAA, are immunodominant in vitro. This phenomenon, which parallels the in vivo immunodominance of certain Ags, implies that the antigenic profile of the cells used for panning determines the specificity of the preponderant population of isolated Abs.

To design products and experiences that are highly intuitive and resonate with their target users the designer must have an accurate understanding of those users ‘mental models’. New research in cognitive science, in particular in the area of cognitive category theory, provides clues how to better elicit and apply mental models in design. The resultant outcome is guaranteed to be more natural and understandable to its users. In this paper we will briefly review the cognitive science research and describe our resultant empirically grounded concept and definition of a ‘mental model’. We then explain how we use the mental model and related design principles to build intuitive designs.

We report the verification of the prediction of chaos in the Portevin–Le Châtelier effect or the jerky flow by analyzing the stress signals obtained from samples of polycrystalline Al–Mg alloys subjected to a constant strain rate test. Particular care is taken to obtain reasonably long and accurate stress signals. The analysis of these signals is carried out by using several complementary methods such as calculation of correlation dimension, singular value decomposition and the spectrum of Lyapunov exponents. The analysis shows the existence of a finite correlation dimension and a positive Lyapunov exponent. Using the existence of a positive Lyapunov exponent and finite correlation dimension as a discriminator, we also carry out a surrogate analysis of the time series to ascertain that the signals are not from a power law stochastic process. The analysis provides an unambiguous support for the existence of chaos in Portevin–Le Châtelier effect thus verifying the prediction of the model. Further, from the analysis we find that the minimum number of variables required for a dynamical description of the jerky flow appears to be four or five consistent with the model.