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Heart failure with preserved ejection fraction (HFpEF) is a disease with a high prevalence. Accounting for more than 50% of all heart failure cases, it carries a significant mortality. There is a lack of therapeutic options that show improvement in morbidity and mortality. Certain novel therapies have shown a decrease in heart failure hospitalizations; however, this beneficial effect was more pronounced for heart failure patients with mildly reduced ejection fraction (EF).This review summarizes the pathophysiology of the disease to help elucidate the differences between heart failure with reduced ejection fraction (HFrEF), and HFpEF, which could explain why therapies are successful in one (rather than the other). This review focuses on non-standardized nomenclature across major trials, the challenges of finding a therapeutic agent for such a heterogeneous population, and identification of specific phenotypes that have different outcomes and could be a target for future therapies.Lack of standardized diagnostic criteria, associated with population heterogeneity, might explain why trials have failed to improve outcomes for patients with HFpEF. Standardizing phenotypes, recapitulating these phenotypes in animal models, and understanding the mechanisms of the disease at the molecular level could be the first steps in identifying promising therapeutic options.

Background: The impact of the new heart allocation policy, which prioritizes acutely ill patients on temporary mechanical circulatory support and provides broader sharing of donor organs, on patient and graft survival in combined heart and kidney transplantation (HKT) is unknown. Methods: In the United Network for Organ Sharing data, patients were divided in groups before and after the policy change (OLD, January 1, 2015 to October 17, 2018, N=533; and NEW, October 18, 2018 to December 31, 2020, N=370). Propensity score matching was performed utilizing recipient characteristics (283 pairs). The median follow-up was 1099 days. Results: The annual volume of HKT increased approximately 2-fold during this period (N=117 in 2015 and N=237 in 2020), predominantly among patients not on hemodialysis at time of transplantation. Ischemic times for heart (OLD, 2.94 versus NEW, 3.37 hours; P P P P P =0.007), and graft failure among HKT recipients (heart, hazard ratio, 1.81; P =0.007; and kidney, hazard ratio, 1.83; P =0.002). Conclusions: The new heart allocation policy was associated with worse overall survival and decreased freedom from heart and kidney graft failure in HKT recipients.

Direct heart transplant from veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support is challenging. Continuation of postoperative VA-ECMO support may be required in the setting of primary graft dysfunction or severe vasoplegia. We describe a simple technique to perfuse the ipsilateral leg of an arterial ECMO cannula during heart transplant while the ECMO circuit is turned off but maintaining the arterial cannula and distal perfusion catheter in place. This technique minimizes the number of intraoperative procedures with a minimal risk of leg ischemia, and provides a smooth transition to postoperative VA-ECMO support if necessary.

Various pharmacotherapies exist for heart failure with preserved ejection fraction (HFpEF), but with unclear comparative efficacy. We searched EMBASE, Medline, and Cochrane Library from inception through August 2021 for all randomized clinical trials in HFpEF (EF40%) that evaluated beta-blockers, mineralocorticoid receptor antagonist (MRA), angiotensin-converting enzyme inhibitors (ACE), angiotensin receptor blockers (ARB), angiotensin receptor-neprilysin inhibitor (ARNI), and sodium-glucose cotransporter-2 inhibitors (SGLT2i). Outcomes assessed were cardiovascular mortality, all-cause mortality, and HF hospitalization. A frequentist network meta-analysis was performed with a random-effects model. We included 22 randomized clinical trials (30,673 participants; mean age = 71.7 ± 4.2 years; females = 49.3 ± 7.7%; median follow-up = 24.4 ± 11.1 months). Compared with placebo, there was no statistically significant difference in cardiovascular mortality [beta-blockers; odds ratio (OR) 0.79 (0.46-1.34), MRA; OR 0.90 (0.70-1.14), ACE OR 0.95 (0.59-1.53), ARB; OR 1.02 (0.87-1.19), ARNI; OR 0.97 (0.74-1.26) and SGLT2i; OR 1.00 (0.84-1.18)] or all-cause mortality [beta blockers; OR 0.75 (0.54-1.04), MRA; OR 0.90 (0.75-1.08) ACE; OR 1.05 (0.71-1.54), ARB; OR 1.03 (0.91-1.15), ARNI; OR 0.99 (0.82-1.20) and SGLT2i; OR 1.00 (0.89-1.13)]. The certainty in these estimates was low or very low. There was a significantly reduction in HF hospitalization with the use of SGLT2i [OR 0.71 (0.62-0.82), moderate certainty], ARNI [OR 0.77 (0.63-0.94), low certainty], and MRA [OR 0.81 (0.66-0.98), moderate certainty]; with corresponding P scores of 0.84, 0.68, and 0.58, respectively. In HFpEF, the use of beta-blockers, MRA, ACE/ARB/ARNI, or SGLT2i was not associated with improved cardiovascular or all-cause mortality. SGLT2i, ARNI, and MRA reduced the risk of HF hospitalizations.

In heart transplantation (HT), peripheral veno-arterial extracorporeal membranous oxygenation (VA-ECMO) is utilized preoperatively as a direct bridge to HT or postoperatively for primary graft dysfunction (PGD). Little is known about wound complications of an arterial VA-ECMO cannulation site which can be fatal.From 2009 to 2021, outcomes of 80 HT recipients who were supported with peripheral VA-ECMO either preoperatively or postoperatively were compared based on the site of arterial cannulation: axillary (AX: N = 49) versus femoral artery (FA: N = 31).Patients in the AX group were older (AX: 59 years vs. 52 years, p = .006), and less likely to have extracorporeal cardiopulmonary resuscitation (0% vs. 12.9%, p = .040). Survival to discharge (AX, 81.6% vs. FA. 90.3%, p = .460), incidence of stroke (10.2% vs. 6.5%, p = .863), VA-ECMO cannulation-related bleeding (6.1% vs. 12.9%, p = .522), and arm or limb ischemia (0% vs. 3.2%, p = .816) were comparable. ECMO cannulation-related wound complications were lower in the AX group (AX, 4.1% vs. FA, 45.2%, p .001) including the wound infections (2.0% vs. 32.3%, p .001). In FA group, all organisms were gram-negative species. In univariate logistic regression analysis, AX cannulation was associated with less ECMO cannulation-related wound complications (Odds ratio, .23, p .001). There was no difference between cutdown and percutaneous FA insertion regarding cannulation-related complications.Given the lower rate of wound complications and comparable hospital outcomes with femoral cannulation, axillary VA-ECMO may be an excellent option in HT candidates or recipients when possible.

Sarcoidosis is a granulomatous disease with the potential of multiple organ system involvement and its etiology remains unknown. Cardiac involvement is associated with worse clinical outcome, and has been reported to be 20%-30% in Caucasian and as high as 58% in Japanese populations with sarcoidosis. Clinical manifestations of cardiac sarcoidosis highly depend on the extent and location of granulomatous inflammation. The most frequent presentations include heart block, tachyarrhythmia, or heart failure. Endomyocardial biopsy is the most specific diagnostic test, but has poor sensitivity due to often patchy involvement. The diagnosis of cardiac sarcoidosis remains challenging due to non-specific imaging findings. Both 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) and cardiac magnetic resonance imaging can be used to evaluate cardiac sarcoidosis, but evaluate different stages of the disease process. FDG-PET detects metabolically-active inflammatory cells while cardiac magnetic resonance imaging with late gadolinium enhancement reveals areas of myocardial necrosis and fibrosis. Aggressive therapy of symptomatic cardiac sarcoidosis is often sought due to the high risk of sudden death and/or progression to heart failure. Prednisone 20-40 mg a day is the recommended initial treatment. In refractory or severe cases, higher doses of prednisone, 1 to 1.5 mg/kg/day (or its equivalent) and addition of a steroid sparing agent have been utilized. Methotrexate is added most commonly. Long-term improvement has been reported with the use of a combination of weekly methotrexate and prednisone versus prednisone alone. After initiation of treatment, a cardiac FDG-PET scan may be performed 2-3 months later to assess treatment response.

Robotic wire arc additive manufacturing (WAAM) technology has been widely employed to fabricate medium to large scale metallic components. It has the advantages of high deposition rates and low cost. Ideally, the deposition process is carried out in a flat position. The build direction is vertically upward and perpendicular to a horizontal worktable. However, it would be difficult to directly deposit complex parts with near horizontal ‘overhangs’, and temporary supports may be required. Thus, it is necessary to find an alternative approach for the deposition of ‘overhangs’ without extra support in order to simplify the deposition set-up. This paper proposed a fabrication method of producing metallic parts with overhanging structures using the multi-directional wire arc additive manufacturing. Firstly, based on the metal droplet kinetics and weld bead geometry, two different Gas Metal Arc Welding (GMAW) metal transfer modes, namely short circuit transfer and free flight transfer, were evaluated for the multi-directional wire arc additive manufacturing. Subsequently, the effects of process parameters, including wire feed speed (WFS), torch travel speed (TS), nozzle to work distance (NTWD) and torch angle, on the stability of positional deposition were investigated. Finally, the effectiveness of the proposed strategy was verified by fabricating three complex samples with overhangs.

There are several endovascular options for temporary mechanical circulatory support in patients with refractory cardiogenic shock. These devices are often utilized in tandem to provide maximal support, including the combination of venoarterial extracorporeal membrane oxygenation with the Impella device, termed ECPELLA. An underappreciated characteristic of mechanical circulatory support is whether they provide cardiac "replacement" and/or cardiac "assistance." Within this framework, we propose an evolution in the approach to ECPELLA utilizing the Impella 5.5, with a focus on the Impella 5.5 as the primary support device.

Background: The study of hypertrophic cardiomyopathy (HCM) can yield insight into the mechanisms underlying the complex trait of cardiac hypertrophy. To date, most genetic variants associated with HCM have been found in sarcomeric genes. Here, we describe a novel HCM-associated variant in the noncanonical Wnt signaling interactor WTIP (Wilms tumor interacting protein) and provide evidence of a role for WTIP in complex disease. Methods: In a family affected by HCM, we used exome sequencing and identity-by-descent analysis to identify a novel variant in WTIP (p.Y233F). We knocked down WTIP in isolated neonatal rat ventricular myocytes with lentivirally delivered short hairpin ribonucleic acids and in Danio rerio via morpholino injection. We performed weighted gene coexpression network analysis for WTIP in human cardiac tissue, as well as association analysis for WTIP variation and left ventricular hypertrophy. Finally, we generated induced pluripotent stem cell–derived cardiomyocytes from patient tissue, characterized size and calcium cycling, and determined the effect of verapamil treatment on calcium dynamics. Results: WTIP knockdown caused hypertrophy in neonatal rat ventricular myocytes and increased cardiac hypertrophy, peak calcium, and resting calcium in D rerio . Network analysis of human cardiac tissue indicated WTIP as a central coordinator of prohypertrophic networks, while common variation at the WTIP locus was associated with human left ventricular hypertrophy. Patient-derived WTIP p.Y233F-induced pluripotent stem cell–derived cardiomyocytes recapitulated cellular hypertrophy and increased resting calcium, which was ameliorated by verapamil. Conclusions: We demonstrate that a novel genetic variant found in a family with HCM disrupts binding to a known Wnt signaling protein, misregulating cardiomyocyte calcium dynamics. Further, in orthogonal model systems, we show that expression of the gene WTIP is important in complex cardiac hypertrophy phenotypes. These findings, derived from the observation of a rare Mendelian disease variant, uncover a novel disease mechanism with implications across diverse forms of cardiac hypertrophy.

Angioembolization (AE) is an adjunct to nonoperative management (NOM) of splenic injuries. We hypothesize that failure of AE is associated with blood transfusion, grade of injury, and technique of AE.We performed a retrospective (2010-2017) multicenter study (nine Level I trauma centers) of adult trauma patients with splenic injuries who underwent splenic AE. Variables included patient physiology, injury grade, transfusion requirement, and embolization technique. The primary outcome was NOM failure requiring splenectomy. Secondary outcomes were mortality, complications, and length of stay.A total of 409 patients met inclusion criteria; only 33 patients (8%) required delayed splenectomy. Patients who failed received more blood in the first 24 h (P = 0.009) and more often received massive transfusion (P = 0.01). There was no difference in failure rates for grade of injury, contrast blush on computed tomography, and branch embolized. After logistic regression, transfusion in the first 24 h was independently associated with failure of NOM (P = 0.02). Patients who failed NOM had more complications (P = 0.002) and spent more days in the intensive care unit (P 0.0001), on the ventilator (P = 0.0001), and in the hospital (P 0.0001). Patients who failed NOM had a higher mortality (15% versus 3%, P = 0.007), and delayed splenectomy was independently associated with mortality (odds ratio, 4.2; 95% confidence interval, 1.2-14.7; P = 0.03).AE for splenic injury leads to effective NOM in 92% of patients. Transfusion in the first 24 h is independently associated with failure of NOM. Patients who required a delayed splenectomy suffered more complications and had higher hospital length of stay. Failure of NOM is independently associated with a fourfold increase in mortality.

Wire arc additive manufacturing (WAAM) is an emerging technology in the manufacturing industry, which uses a welding arc as an energy source to fuse metal wire and deposit layer by layer. In order to promote its manufacture precision, stability, and repeatability, it’s crucial to develop a feedback control strategy for WAAM. This research implements vision-based feedback control for the layer width during the WAAM process. A WAAM system is developed using a robot and CMT welder with a visual sensing system. The dynamics of the layer width in WAAM process is modeled experimentally. An ARX dynamic model is built. Based on this model, a model predictive control (MPC) strategy is derived to regulate the WAAM process. Feedback control experiments were conducted to verify the tracking and robustness performance of the proposed MPC algorithm.

Wire arc additive manufacturing technology (WAAM) has become a very promising alternative to high-value large metal components in many manufacturing industries. Due to its long process cycle time and arc-based deposition, defect monitoring, process stability and control are critical for the WAAM system to be used in the industry. Although major progress has been made in process development, path slicing and programming, and material analysis, a comprehensive process monitoring, and control system are yet to be developed. This paper aims to provide an in-depth review of sensing and control design suitable for a WAAM system, including technologies developed for the generic Arc Welding process, the Wire Arc Additive Manufacturing process and laser Additive Manufacturing. Particular focus is given to the integration of sensor-based feedback control, and how they could be implemented into the WAAM process to improve its accuracy, reliability, and efficiency. The paper concludes by proposing a framework for sensor-based monitoring and control system for the GMAW based WAAM process. This framework provides a blueprint for the monitoring and control strategies during the WAAM process and aims to identify and reduce defects using information fusion techniques.

FeNi intermetallic has been continuously attractive due to the appreciable magneto-crystalline anisotropy and high saturation magnetization in the nominally-equiatomic chemically ordered L10 structure. In the present research, the bulk FeNi alloy is successfully fabricated using an innovative wire-arca additive manufacturing process, which is also an in-situ alloying method. In the meantime, to characterize the thermal lattice evolution of the FeNi, neutron diffraction is conducted to the as-fabricated sample in-situ during a heat treatment process. According to the neutron results, an anisotropic fcc-FeNi lattice evolution has been detected, which indicates the existence of FeNi superstructure in the WAAM fabricated FeNi bulk material. In addition, due to the featured advantage of the neutron data, the fcc-FeNi volumetric lattice thermal expansion coefficients during heating and cooling processes are calculated.

Wire arc additive manufacturing (WAAM) is a Direct Energy Deposition (DED) technology, which utilize electrical arc as heat source to deposit metal material bead by bead to make up the final component. However, issues like the lack of assurance in accuracy, repeatability and stability hinder the further application in industry. Therefore, a Model Free Adaptive Iterative Learning Control (MFAILC) algorithm was developed to be applied in WAAM process in this study. The dynamic process of WAAM is modelled by adaptive neuro fuzzy inference system (ANFIS). Based on this ANFIS model, simulations are performed to demonstrate the effectiveness of MFAILC algorithm. Furthermore, experiments are conducted to investigate the tracking performance and robustness of the MFAILC controller. This work will help to improve the forming accuracy and automatic level of WAAM.

As an advanced and highly efficient welding method, Keyhole Tungsten Inert Gas (keyhole TIG) welding has drawn wide interests from the manufacturing industry. In order to improve its manufacturing quality and automation level, it’s necessary to develop an online monitoring system for the keyhole TIG welding process. This study developed a visual monitoring system, which utilized an HDR welding camera to monitor the welding pool and keyhole during keyhole TIG welding process. A state of the art Convolutional neural network (Resnet) was developed to recognize different welding states, including good weld, incomplete penetration, burn through, misalignment and undercut. In order to improve the diversity of training dataset, image augmentation was performed. To optimize the training process, a metric learning strategy of center loss was introduced. Furthermore, visualization methods, including guided Grad-CAM, feature map and t-SNE were applied to understand and explain the effectiveness of deep learning process. This study will lay a solid foundation for the development of on-line monitoring system of keyhole TIG.

The present study centres on the effect of post-weld heat treatment (PWHT) on microstructure and mechanical properties of the deep penetration keyhole Tungsten Inert Gas (K-TIG) welded dissimilar joint between creep strength enhanced ferritic (CSEF) steel and austenitic stainless steel (ASS). The as-received normalized and tempered CSEF steel was joined with ASS in a single pass without using any filler materials and edge preparation. Detailed characterization across the welded joint was conducted using stereomicroscope, electron microscopy, energy dispersive spectroscopy (EDS), electron backscattered diffraction (EBSD), hardness test, tensile test and Charpy impact test. Results showed that PWHT had significant effect on the microstructure and mechanical properties of both the weld metal and CSEF steel heat-affected zone (HAZ), while it had little influence on the ASS side. By using proper PWHT, the hardness gradient across the welded joint could be mitigated and toughness in both the weld metal and the CSEF steel HAZ could be restored. 760 °C was considered the most appropriate PWHT temperature for such dissimilar joint in terms of the overall mechanical properties. The tensile properties of K-TIG welded joint after PWHT were comparable to both friction stir welded joint and laser and/or electron beam welded joint, indicating that deep penetration TIG welding technology may provide a good alternative for the nuclear industry. The correlation among welding thermal cycle, various heat treatment, microstructure evolution and mechanical properties was also analysed in detail.

Background: Coronary angiography to identify coronary artery disease has been foundational to distinguish the cause of dilated cardiomyopathy (DCM), including the assignment of idiopathic or ischemic cardiomyopathy. Late gadolinium enhancement (LGE) with cardiovascular magnetic resonance (CMR) has emerged as an approach to identify myocardial scar and identify etiology. Methods: The DCM Precision Medicine Study included patients with left ventricular dilation and dysfunction attributed to idiopathic DCM, after expert clinical review excluded ischemic or other cardiomyopathies. Ischemic cardiomyopathy was defined as coronary artery disease with >50% narrowing at angiography of ≥1 epicardial coronary artery. CMR was not required for study inclusion, but in a post hoc analysis of available CMR reports, patterns of LGE were classified as (1) no LGE, (2) ischemic-pattern LGE: subendocardial/transmural, (3) nonischemic LGE: midmyocardial/epicardial. Results: Of 1204 idiopathic DCM patients evaluated, 396 (32.9%) had a prior CMR study; of these, 327 (82.6% of 396) had LGE imaging (mean age 46 years; 53.2% male; 55.4% White); 178 of the 327 (54.4%) exhibited LGE, and 156 of the 178 had LGE consistent with idiopathic DCM. The remaining 22 had transmural or subendocardial LGE. Of these 22, coronary angiography was normal (13), showed luminal irregularities (3), a distant thrombus (1), coronary artery disease with Conclusions: Of 327 probands enrolled in the DCM Precision Medicine Study cohort who had LGE-CMR data available, an ischemic-pattern of LGE was identified in 22 (6.7%), all of whom had idiopathic DCM as adjudicated by expert clinical review. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03037632.

Idiopathic dilated cardiomyopathy (DCM) aggregates in families, and early detection in at-risk family members can provide opportunity to initiate treatment prior to late-phase disease. Most studies have included only White patients, yet Black patients with DCM have higher risk of heart failure-related hospitalization and death.To estimate the prevalence of familial DCM among DCM probands and the age-specific cumulative risk of DCM in first-degree relatives across race and ethnicity groups.A family-based, cross-sectional study conducted by a multisite consortium of 25 US heart failure programs. Participants included patients with DCM (probands), defined as left ventricular systolic dysfunction and left ventricular enlargement after excluding usual clinical causes, and their first-degree relatives. Enrollment commenced June 7, 2016; proband and family member enrollment concluded March 15, 2020, and April 1, 2021, respectively.The presence of DCM in a proband.Familial DCM defined by DCM in at least 1 first-degree relative; expanded familial DCM defined by the presence of DCM or either left ventricular enlargement or left ventricular systolic dysfunction without known cause in at least 1 first-degree relative.The study enrolled 1220 probands (median age, 52.8 years [IQR, 42.4-61.8]; 43.8% female; 43.1% Black and 8.3% Hispanic) and screened 1693 first-degree relatives for DCM. A median of 28% (IQR, 0%-60%) of living first-degree relatives were screened per family. The crude prevalence of familial DCM among probands was 11.6% overall. The model-based estimate of the prevalence of familial DCM among probands at a typical US advanced heart failure program if all living first-degree relatives were screened was 29.7% (95% CI, 23.5% to 36.0%) overall. The estimated prevalence of familial DCM was higher in Black probands than in White probands (difference, 11.3% [95% CI, 1.9% to 20.8%]) but did not differ significantly between Hispanic probands and non-Hispanic probands (difference, -1.4% [95% CI, -15.9% to 13.1%]). The estimated prevalence of expanded familial DCM was 56.9% (95% CI, 50.8% to 63.0%) overall. Based on age-specific disease status at enrollment, estimated cumulative risks in first-degree relatives at a typical US advanced heart failure program reached 19% (95% CI, 13% to 24%) by age 80 years for DCM and 33% (95% CI, 27% to 40%) for expanded DCM inclusive of partial phenotypes. The DCM hazard was higher in first-degree relatives of non-Hispanic Black probands than non-Hispanic White probands (hazard ratio, 1.89 [95% CI, 1.26 to 2.83]).In a US cross-sectional study, there was substantial estimated prevalence of familial DCM among probands and modeled cumulative risk of DCM among their first-degree relatives.ClinicalTrials.gov Identifier: NCT03037632.

Motivated by increasing productivity and cost-effectiveness, the feasibility of Keyhole Tungsten Inert Gas (K-TIG) welding for joining SAF2205/AISI316L dissimilar materials was presented. Single pass autogenous welding was achieved on 5.6 mm thick plates at a speed of 35 cm/min without using any filler materials and edge preparation. In-depth investigation into the weld was conducted by optical microscope, scanning electron microscope, Thermo-Calc simulation, microhardness, tensile test and impact toughness test. The results show that in order to produce defect free dissimilar joint, the torch deviation should be kept at zero to one mm towards AISI316L side. The austenite fraction increased with torch deviation shifted from SAF2205 side to AISI316L side, along with the variation in ferrite morphology from massive type to lath shape. Defect free joints possess better tensile properties than AISI316L base metal, indicating sufficient strength level for such dissimilar joint. Poorer toughness of the samples with 1 mm torch deviation towards SAF2205 side and 2 mm deviation towards 316L side is a result of imbalanced phase structure, ferritic-asutenitic solidification mode as well as harmful precipitates in the weld. It has been demonstrated that the K-TIG welding process offers an efficient way to produce sound and high quality dissimilar joint between SAF2205 and AISI316L, with 0–1 mm torch deviation towards 316L side being the desired options in terms of overall material properties.

Hydrogen has been considered as a potential candidate for the replacement of fossil fuels in future due to its renewability, abundance, ease in production, environmental friendliness and high energ...

Robots are widely used in automation because of their flexibility. However, there are still challenges to enhance the effective use of robots in machining process due to unexpected vibration/chatter. Instead of time-consuming trial and error, this paper proposes an expanded mode coupling chatter theory that suits robot kinematics and enables industrial application due to accurate mode coupling chatter prediction. This research allows determination of mode coupling chatter occurrence with respect to constantly changing parameters of robotic kinematic and practical contemplation before setting up the physical robot, workpiece and tool for machining. Firstly, the mathematical model of the robot structure is established and combined with chatter theory. A deepened analysis of stability criteria is carried out followed by experimental validation of the theory. By carrying out this chatter analysis, a software tool based on an algorithm was developed to help determine the stable setup, including machining parameters, robot pose, travel direction and workpiece setup, for a certain robotic machining application. The developed prediction algorithm ties vibration occurrence to machining force direction and magnitude that makes it applicable to various machining operations.

In order to introduce vanadium as a ternary alloying element during the wire arc additive manufacturing (WAAM) of titanium aluminide intermetallic alloys, alloy and elemental wire consumables (Ti6Al4V and Al wires, respectively) were used with the WAAM process. A crack-free TiAl bulk with nominal chemical composition of Ti45Al2.2 V was successfully fabricated for the first time through dynamic in situ alloying using WAAM method. The experimental results showed that the introduction of V from Ti6Al4V alloy does not change the flat features of lamellar interface and also does not alter the phase composition of the resultant TiAl alloy. The fabricated Ti45Al2.2 V alloy consists of lamellar colonies and γ interdendritic phase in the top region, fully lamellar structure with unclear grain boundaries in the band regions and large equiaxed α2 with fine γ laths precipitated at grain boundaries in the layers. The microhardness and tensile properties were greatly increased by introducing V due to the general absence of interdendritic γ phase and the V ductilization effect. In addition, the influences of two-step post-heat treatments on the microstructure and mechanical properties are analysed. Results indicate that the microstructure and mechanical properties of the fabricated alloy can be considerably modified after applying different solution treatment temperatures.

TiAl intermetallic compounds were deposited using in-situ alloying with the dual-wire arc additive manufacturing method, and their material properties were investigated. The compounds were designed with different phase constituents and microstructure, achieved through adjusting the elemental wire feed rates according to atomic ratios of Ti: Al = 65%: 35%, 55%: 45%, and 45%: 55%, respectively. Single α2-Ti3Al and γ-TiAl phases were obtained with compositions of Ti-35%Al and Ti-55%Al, while Ti-45%Al resulted in the phase composed of γ-TiAl and α2-Ti3Al. Additionally, the influence of phase composition and microstructure on mechanical properties and oxidation behaviour of the fabricated materials were studied and analysed. In conclusion, the phase composition of TiAl intermetallic alloys could be readily controlled using the dual-wire WAAM method and acceptable properties could be obtained.

γ-phase based titanium aluminide has continuously been attractive because of its potential application in modern light-weight, high-temperature turbines, such as aircraft engines. However, it suffers from its poor plasticity and during manufacturing and processing. In recent years, wire-arc additive manufacturing process has been proved feasible of fabricating γ-phase based titanium aluminide structures with full density and relatively lower cost compared to traditional powder metallurgy processing. In the present research, the temperature process of a single-pass deposition process during the additive manufacturing was simulated as a linear heating (up to 1623 K) and cooling process in a vacuumed furnace, and in-situ investigated using neutron diffraction. As a result, compared to the initial as-fabricated state, the volume fraction of α2-phase increased by 2.54% after the heat treatment. Crystallographic aspects, specifically the α/α2 ↔ γ phase transformation and lattice evolutions of γ-phase are discussed in detail. According to the results obtained, the γ → α2 transition temperature in the present binary alloy is 1393 K, which largely deviates from earlier results collected from γ-phase based titanium aluminides with Nb addition. Also, the lattice evolutions of γ-phase in a function of time/temperature are linear fitted and responses of lattice strains (a, c axis and volumetric) to temperature are calculated.

Ni-rich NiTi alloy was successfully fabricated for the first time using wire arc additive manufacturing (WAAM) technique. The distinct anisotropic microstructure with increased amount of Ni4Ti3 but decreased amount of Ni3Ti from lower to upper region leads to obviously decreasing transformation temperature, increasing hardness and tensile strength but reduced ductility.

BackgroundImaging repositories are commonly attached to ongoing clinical trials for efficiency and cost savings, but capturing, transmitting and storing images can be cumbersome and increase costs. Typical methods include outdated technologies such as compact discs. Electronic file transfer is becoming more common, but even this requires hours of staff time on dedicated computers in the radiology department.MethodsWe describe and test an image capture method using smartphone camera video images of brain computed tomography (CT) scans of traumatic intracranial hemorrhage. The deidentified videos are emailed from the emergency department for central adjudication. We selected eight scans, mild moderate and severe subdural and multicompartmental hematomas and mild and moderate intraparenchymal hematomas. Eighty videos were made by 10 people on 7 different smartphones. We measured the time in seconds it took to capture and email the files. The primary outcomes were hematoma volume measured by ABC/2, Marshal Scale, midline shift measurement, image quality by contrast-to-noise ratio (CNR) and time to capture. A radiologist and an imaging scientist applied ABC/2 method, calculated the Marshall scale and midline shift on the video images and on the PACS in a randomized order. We calculate the intraclass correlation coefficient (ICC). We measured image quality by calculating contrast-to-noise ratio (CNR). We report summary statistics on time to capture in the smartphone group without a comparator.ResultsICC for lesion volume, midline shift and Marshall score were 0.991 (95% CI 0.976, 0.998), 0.998 (95% CI: 0.996, 0.999) and 0.973 (0.931, 0.994) respectively. Lesion conspicuity was not different among the image types via assessment of CNR using the Friedman test, Bof 10.6, P=.061, with a small Kendall’s W effect size (0.264). Mean (standard deviation) time to capture and email the video was 60.1 (24.3) seconds.ConclusionsTypical smartphones may produce video image quality high enough for use in a clinical trial imaging repository. Video capture and transfer takes only seconds, and hematoma volumes, Marshal scales and image quality measured on the videos did not differ significantly from those calculated on the PACS.

Specific aetiologies of cardiomyopathy can significantly impact treatment options as well as appropriateness and prioritisation for advanced heart failure therapies such as ventricular assist device (VAD) or orthotopic heart transplantation (OHT). We reviewed the tissue diagnoses of patients who underwent advanced therapies for heart failure (HF) to identify diagnostic discrepancies.This study presents a retrospective cohort of the aetiology of cardiomyopathy in 118 patients receiving either durable VAD or OHT. Discrepancies between the preoperative aetiological diagnosis of cardiomyopathy with the pathological diagnosis were recorded. Echocardiographic and haemodynamic data were reviewed to examine differences in patients with differing aetiological diagnoses.Twelve (12) of 118 (12/118) (10.2%) had a pathological diagnosis that was discordant with pre-surgical diagnosis. The most common missed diagnoses were infiltrative cardiomyopathy (5) and hypertrophic cardiomyopathy (3). Patients with misidentified aetiology of cardiomyopathy had smaller left ventricular (LV) dimensions on echocardiography than patients with dilated cardiomyopathy (5.8±0.9 vs 6.7±1.1 respectively p=0.01).Most HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, but a missed diagnosis at time of intervention (VAD or OHT) was not uncommon. Smaller LV dimension on echocardiogram in a patient with a non-ischaemic cardiomyopathy warrants further workup for a more specific aetiology.

Left ventricular assist device (LVAD) implantation in patients with advanced heart failure due to hypertrophic or restrictive cardiomyopathy (HCM/RCM) presents technical and physiologic challenges. We conducted a systematic review of observational studies to evaluate the utilization and clinical outcomes associated with LVAD implantation in patients with HCM/RCM and compared these to patients with dilated or ischemic cardiomyopathy (DCM/ICM). We searched MEDLINE, EMBASE, and Scopus from inception through May 2019 and included appropriate studies describing the use of an LVAD in patients with HCM/RCM. We identified six studies with a total of 2,766 patients with HCM/RCM and advanced heart failure, among whom 338 patients (12.2%) underwent LVAD implantation. In patients listed for transplant, the rate of LVAD implantation was significantly lower in patients with HCM/RCM compared to that in patients with DCM/ICM (4.4% vs. 18.2%, p < 0.001). Adverse clinical outcomes were significantly higher in HCM/RCM than in DCM/ICM, including operative/short-term mortality (14.0% vs. 9.0%), right ventricular failure (50.0% vs. 21.0%), infection (15.5% vs. 11.2%), bleeding (40.2% vs. 12.5%), renal failure (15.0% vs. 5.1%), stroke (5.0% vs. 2.4%), and arrhythmias (18.0% vs. 7.7%) (all p values

Accurate side-channel attacks can non-invasively or semi-invasively extract secure information from hardware devices using "side- channel" measurements. The thermal profile of an IC is one class of side channel that can be used to exploit the security weaknesses in a design. Measurement of junction temperature from an on-chip thermal sensor or top metal layer temperature using an infrared thermal image of an IC with the package being removed can disclose secret keys of a cryptographic design through correlation power analysis. In order to identify the design vulnerabilities to thermal side channel attacks, design time simulation tools are highly important. However, simulation of thermal side-channel emission is highly complex and computationally intensive due to the scale of simulation vectors required and the multi-physics simulation models involved. Hence, in this paper, we have proposed a fast and comprehensive Machine Learning (ML) augmented thermal simulation methodology for thermal Side-Channel emission Analysis (SCeA). We have developed an innovative tile-based Delta-T Predictor using a data-driven DNN-based thermal solver. The developed tile based Delta-T Predictor temperature is used to perform the thermal side-channel analysis which models the scenario of thermal attacks with the measurement of junction temperature. This method can be 100-1000x faster depending on the size of the chip compared to traditional FEM-based thermal solvers with the same level of accuracy. Furthermore, this simulation allows for the determination of location- dependent wire temperature on the top metal layer to validate the scenario of thermal attack with top metal layer temperature. We have demonstrated the leakage of the encryption key in an 128-bit AES chip using both proposed tile-based temperature calculations and top metal wire temperature calculations, quantified by simulation MTD (Measurements-to-Disclosure).