Primary Arm Research Articles

Blue light transurethral resection and biopsy of bladder cancer with hexaminolevulinate: Histopathological characteristics and recurrence rates in a single UK centre study.

Blue light cystoscopy with hexaminolevulinate (HAL) during transurethral resection of bladder cancer (TURBT) has been shown to improve detection, thereby reducing bladder cancer recurrence compared with white light cystoscopy. Single-centred UK (United Kingdom) study on 101 patients who underwent blue light cystoscopy between July 2017 and November 2020, performed by a single surgeon. Our study was divided into two arms; the primary arm had no prior diagnosis of bladder malignancy (N= 41), whereas secondary re-resection arm had (N= 57). Three patients with non-urothelial bladder cancer were excluded. Patients were followed up for 24 months. Data were collected on biopsy quality, histopathological characteristics and recurrence. The end points of the study were recurrence rate at 24 months in both arms and detection of CIS in patients who undergo TURBT or biopsy after initial white light study in the secondary, re-resection arm. This was analysed with Fisher's exact test. Of 98 patients, 39 had malignancy in their first blue light TURBT/biopsy: primary arm (10/41, 24.4%) and secondary arm (29/57, 50.9%), with detrusor present in 80.5% and 80.7%, respectively. In the secondary arm, blue light re-resection TURBT detected significantly more CIS (20.7% vs 51.7%, p= 0.0277) compared with white light with 3.4% upstaged to muscle invasive bladder cancer (G3pT2). Median time to re-resection was 3.06 months. Recurrence rate was 33.3% in the primary arm and 37.5% in the secondary arm after 24 months of follow-up. Our data confirm that blue light TURBT with HAL provides superior detection and diagnosis of CIS in patients with previous white light cystoscopy.

High-performance GPU computing of phase-field lattice Boltzmann simulations for dendrite growth with natural convection

The effect of natural convection on dendrite morphology is investigated through three-dimensional large-scale phase-field lattice Boltzmann simulations using a block-structured adaptive mesh refinement scheme with the mother-leaf method in a parallel-GPU environment. The simulations confirmed that downward buoyancy enhances the growth of the primary and secondary arms, and upward buoyancy delays the growth of those arms. In addition, the effect of natural convection on the solidification morphologies gradually decreased as the primary arm tip reached the top of the computational domain and finally stopped. Furthermore, in the longer simulation under purely isothermal diffusive conditions, detachment of the secondary arms owing to curvature-driven fragmentation was observed. A large-scale non-isothermal dendrite growth simulation was also conducted, wherein it was observed that the tip growth rate of the primary arm was delayed, and the secondary arm spacing was larger than that in the isothermal condition.

Left Ventricular Global Longitudinal Strain Following Acute ST-Elevation Myocardial Infarction - A Comparison of Primary Coronary Angioplasty and Tenecteplase-Based Pharmacological Reperfusion Strategy.

In the setting of acute ST-elevation myocardial infarction (STEMI), reperfusion therapy with primary percutaneous coronary intervention (PCI) performed by an experienced team or pharmacological reperfusion with thrombolytic therapy is highly recommended. Standard echocardiographic measurement of the left ventricular ejection fraction (LVEF) is widely used to assess left ventricular global systolic function. This study was designed to compare the assessment of global left ventricular function by standard LVEF and global longitudinal strain (GLS) in the two well-known reperfusion strategies. We conducted a retrospective single-center observational study in 50 patients with acute STEMI who underwent primary PCI (n = 25) and Tenecteplase (TNK)-based pharmacological reperfusion therapy (n = 25). The primary outcome was left ventricle (LV) systolic function after primary PCI, as assessed by two-dimensional (2D) GLS using speckle-tracking echocardiography (STE), as well as LVEF using standard 2D echocardiogram using Simpson's biplane method. Overall mean age was 53.7 ± 6.9 years with 88% male gender. The mean door-to-needle time was 29.8 ± 4.2 min in the TNK-based pharmacological reperfusion therapy arm, and the mean door-to-balloon time was 72.9 ± 15.4 min in the primary PCI arm. LV systolic function was significantly better in the primary PCI arm as compared to the TNK-based pharmacological reperfusion therapy, both by 2D STE (mean GLS: -13.6 ± 1.4 vs. -10.3 ± 1.2, P ≤ 0.001) and LVEF (mean LVEF: 42.2 ± 2.9 vs. 39.9 ± 2.7, P = 0.006). There were no significant differences in mortality and inhospital complications in both groups. Global LV systolic function is significantly better after primary coronary angioplasty as compared to TNK-based pharmacological reperfusion therapy when assessed by routine LVEF and 2D GLS in the setting of acute STEMI.

The Mechanism of Dendrite Formation in a Solid-State Transformation of High Aluminum Fe-Al Alloys.

The mechanism of solid-state dendrite formation in high-aluminum Fe-Al alloys is not clear. Applying an in-situ observation technique, the real-time formation and growth of FeAl solid-state dendrites during the eutectoid decomposition of the high-temperature phase Fe5Al8 is visualized. In-situ experiments by HT-CSLM reveal that proeutectoid FeAl usually does not preferentially nucleate at grain boundaries regardless of rapid or slow cooling conditions. The critical radii for generating morphological instability are 1.2 μm and 0.9 μm for slow and rapid cooling, respectively. The morphology after both slow and rapid cooling exhibits dendrites, while there are differences in the size and critical instability radius Rc, which are attributed to the different supersaturation S and the number of protrusions l. The combination of crystallographic and thermodynamic analysis indicates that solid-state dendrites only exist on the hypoeutectoid side in high-aluminum Fe-Al alloys. A large number of lattice defects in the parent phase provides an additional driving force for nucleation, leading to coherent nucleation from the interior of the parent phase grains based on the orientation relationship {3¯30}Fe5Al8//{1¯10}FeAl, <111¯>Fe5Al8//<111¯>FeAl. The maximum release of misfit strain energy leads to the preferential growth of the primary arm of the nucleus along <111¯> {1¯10}. During the rapid cooling process, a large supersaturation is induced in the matrix, driving the Al atoms to undergo unstable uphill diffusion and causing variations in the concentration gradient as well as generating constitutional undercooling, ultimately leading to morphological instability and the growth of secondary arms.

Differences in Post Ablation Cardiac MRI Scar Between Radiofrequency and Cryoballoon Ablation: A DECAAF II Sub-analysis.

Pulmonary vein isolation (PVI) using radiofrequency (RF) and cryoballoon (Cryo) ablation are standard approaches for rhythm control in patients with symptomatic atrial fibrillation. Both strategies create scar in the left atrium (LA). There have been few studies investigating the difference in scar formation between patients undergoing RF and Cryo using cardiac magnetic resonance imaging (CMR). The current study is a sub-analysis of the control arm of the Delayed-Enhancement MRI Determinant of Successful Catheter Ablation of Atrial Fibrillation study (DECAAF II). The study was a multicenter, randomized, controlled, single blinded trial that evaluated atrial arrhythmia recurrence (AAR) between PVI alone and PVI plus CMR atrial fibrosis guided ablation. Pre-ablation CMR and 3-6-month post ablation CMR were obtained to assess baseline LA fibrosis and scar formation respectively. Of the 843 patients randomized in the DECAAF II trial, we analyzed the 408 patients in the primary analysis control arm that received standard PVI. Five patients received combined RF and Cryo ablations so were excluded from this sub-analysis. Of the 403 patients analyzed, 345 underwent RF and 58 Cryo. The average procedure duration was 146 minutes for RF and 103 minutes for Cryo (p = 0.001). The rate of AAR at ~15 months occurred in 151 (43.8%) patients in the RF group and 28 (48.3%) patients in the Cryo group (p = 0.62). On 3-month post CMR the RF arm had significantly more scar (8.8% vs. 6.4%, p = 0.001) compared to Cryo. Patients with ≥ 6.5% LA scar (p < 0.001) and ≥ 2.3% LA scar around the PV antra (p = 0.01) on 3-month post CMR had less AAR independent of ablation technique. Cryo caused a greater percentage of right and left pulmonary vein (PV) antral scar (p = 0.04, p = 0.02) and less non-PV antral scar (p = 0.009) compared to RF. On Cox regression Cryo patients free of AAR had a greater percentage of left PV antral scar (p = 0.01) and less non-PV antral scar (p = 0.004) compared to RF free of AAR. In this sub-analysis of the control arm of the DECAAF II trial, we observed that Cryo formed a greater percentage of PV antral scar and less non-PV antral scar compared to RF. Post ablation LA scar ≥ 6.5% predicted freedom from AAR, independent of ablation technique. These findings may have prognostic implications in ablation technique selection and freedom from AAR. This article is protected by copyright. All rights reserved.

The relationship between electric processing condition and microstructure in the solidification of multicomponent oxides

Systematic characterization for the relationship between the electropulse processing conditions and microstructure has been carried out in the present work. It is found that electropulse can refine porosity and alter grain morphology considerably. A processing with optimum electropulsing parameters can reduce over 75% volume fraction of porosity and more than 70% average pore diameter in comparison with that of reference sample without electric treatment. Electric current treatment promotes the growth of dendrites with smaller thickness of primary arms dendrite and prevents the liquid entrapping between the growing solid grains. The former is caused by the effect of electricity-enhanced kinetic mobility on the radius of curvature at the tip of dendrite. The latter is attributed to the effects of electric thermodynamics on the microstructural formation such as the enhanced connectivity of conductive phase. The microstructures obtained by electropulsing treatment are favourable for heat conduction, structural strength and crack prohibition. However, the excess pulse frequency and pulse width can generate unwanted heat to counteract electric effect. The research reveals the relationship between electric processing conditions and microstructure in a perfectly controversial solidification condition in oxide materials to that of the metals and alloys. The results confirm from the opposite side the validity of the pulsated solidification.

Towards a sustainable bioeconomy in a post-oil era Nigeria

The bioeconomy comprises all primary arms of production, including industrial and economic sectors that employ biological resources and techniques to generate bio-based products and services, while creating new industries and employment. Advocates of the bioeconomy anticipate that biotechnology will play a key role in its development via scientific advances that will spur innovations in deriving products and energy from renewable biomass. About 50 countries have adopted bioeconomy policies, with a view to unlocking new vistas for economic development and innovation, while pushing towards the attainment of the United Nations Sustainable Development Goals (SDGs). Nigeria has an estimated annual biomass potential of about 200 billion kilogrammes, which could be harnessed to generate biofuels via integrated bio-refineries and microbial conversion. In addition, alternative food sources from microorganisms, aquaponics and other products from wood, especially as a plastic alternative and medicines provide endless opportunities for a sustainable bioeconomy in Nigeria. • Nigeria is and has been in a post-oil era. • Nigeria has an estimated annual biomass potential of about 200 billion kilogrammes. • Nigeria’s lignocellulosic biomass could be harnessed for the sustainable production of high-performance bioplastics and wood-derived hydrogels for targeted and controlled drug-delivery platforms. • Nigeria’s bioeconomy can drive more resilient economic growth and create job opportunities.

Enhanced cooling rates in laser directed energy deposition with interlayer peening

PurposeThis study aims to investigate the effect of mechanical peening on the cooling rate of a subsequently deposited layer in a hybrid additive manufacturing (AM) process.Design/methodology/approachIn this experimental study, 20 layers of 316 L stainless steel are built via directed energy deposition, with the tenth layer being subject to various peening processes (shot peening, hammer peening and laser shock peening). The microstructure of the eleventh layer of all the samples is then characterized to estimate the cooling rate.FindingsThe measurements indicate that the application of interlayer peening causes a reduction in primary cellular arm spacing and an increase in micro segregation as compared to a sample prepared without interlayer peening. Both factors indicate an increase in the cooling rate brought about by the interlayer peening.Practical implicationsThis work provides insight into process design for hybrid AM processes as cooling rates are known to influence mechanical properties in laser-based AM.Originality/valueTo the best of the authors’ knowledge, this work is the first of its kind to evaluate the effects of interlayer peening on a subsequently deposited layer in a hybrid AM process.

Primary tumour side as a driver for treatment choice in RAS wild-type metastatic colorectal cancer patients: a systematic review and pooled analysis of randomised trials

BackgroundRetrospective subgroup analyses of previous trials in the first-line therapy of RAS wt metastatic colorectal cancer (mCRC) suggested a predictive impact of primary tumour side on the efficacy of anti-epidermal growth factor receptor (EGFR) agents. Recently, new head-to-head trials of doublets/bevacizumab versus doublets/anti-EGFR, PARADIGM and CAIRO5 were presented. Patients and methodsWe searched for phase II and III trials comparing doublet chemotherapy plus an anti-EGFR or bevacizumab as the first-line treatment for RAS wt mCRC patients. Overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and radical resection rate result in the overall study populations and, according to the primary side, were pooled together in a two-stage analysis with random effects and fixed effect models. The interaction between sidedness and treatment effect was then analysed. ResultsWe identified five trials (PEAK, CALGB/SWOG 80405, FIRE-3, PARADIGM and CAIRO5), including 2739 patients, 77% left- and 23% right-sided. Among patients with left-sided mCRC, the use of anti-EGFRs was associated with higher ORR (74% versus 62%, OR = 1.77 [95% confidence interval {CI} 1.39–2.26–0.88], p < 0.0001), longer OS (hazard ratio [HR] = 0.77 [95% CI 0.68–0.88], p < 0.0001) and not significantly longer PFS (HR = 0.92, p = 0.19). Among patients with right-sided mCRC, the use of bevacizumab was associated with longer PFS (HR = 1.36 [95% CI 1.12–1.65], p = 0.002) and not significantly longer OS (HR = 1.17, p = 0.14). A subgroup analysis confirmed a significant interaction effect between the primary tumour side and treatment arm in terms of ORR (p = 0.02), PFS (p = 0.0004) and OS (p = 0.001). No differences in the radical resection rate were found according to treatment and sidedness. ConclusionsOur updated metanalysis corroborates the role of the primary tumour location in the choice of the upfront therapy for RAS wt mCRC patients, leading to strongly recommend anti-EGFRs in left-sided tumours and to prefer bevacizumab in the right-sided.

Investigation of Al-20Sn-10Cu alloy directional solidification by laboratory X-radiography

Al-based alloys with a soft phase such as Sn are extensively used for bearing components due to their self-lubricating properties. Al-Sn alloys lack the ability to support heavy loads so the alloying with Cu as a third element provides solution strengthening of the aluminium matrix. A crucial issue in the manufacturing of Al-Sn-Cu alloys is the miscibility gap in the phase diagram of the system. Liquid immiscibility is responsible for severe segregation during the solidification process, due to the large density difference between the Al-rich and Sn-rich liquids, which limits their utilization in industry. It is therefore both scientifically and technically important to accurately understand their solidification path. In the present work, the solidification of a ternary Al-20wt.%Sn-10wt.%Cu alloys was investigated in-situ by using X-radiography. Directional solidification experiments were performed on sheet-like samples in the laboratory device SFINX (Solidification Furnace with IN-situ X-radiography), which consists of a Bridgman-type gradient furnace and an X-radiography system. The solidification sequence was determined based on the observation of the recorded images, enlightening the successive steps of the solidification path. These observations were compared to predictions obtained from thermodynamic calculations. Complementary post-mortem microscopic analyses showed that the dendrite primary trunk and secondary arms developed along <110> crystallographic axes instead of the usually expected <100>.

Preliminary system for data assimilation to infer material parameters from directional solidification experiments: twin experimental study using phase-field method

The integration of phase-field (PF) simulations and in situ observations is a promising approach for understanding dendrite growth. In this study, a preliminary data assimilation system is developed to integrate PF simulations and in situ real-time X-ray radiography during the directional solidification of a binary alloy. In this system, only the region around the tip of a primary arm is used for data assimilation. The validity of the developed system is confirmed through twin experiments for columnar dendrite growth with different inclined angles of preferred growth direction.

Magnetic field-assisted solidification of W319 Al alloy qualified by high-speed synchrotron tomography

Magnetic fields have been widely used to control solidification processes. Here, high-speed synchrotron X-ray tomography was used to study the effect of magnetic fields on solidification. We investigated vertically upward directional solidification of an Al-Si-Cu based W319 alloy without and with a transverse magnetic field of 0.5 T while the sample was rotating. The results revealed the strong effect of a magnetic field on both the primary α-Al phase and secondary β-Al5FeSi intermetallic compounds (IMCs). Without the magnetic field, coarse primary α-Al dendrites were observed with a large macro-segregation zone. When a magnetic field is imposed, much finer dendrites with smaller primary arm spacing were obtained, while macro-segregation was almost eliminated. Segregated solutes were pushed out of the fine dendrites and piled up slightly above the solid/liquid interface, leading to a gradient distribution of the secondary β-IMCs. This work demonstrates that rotating the sample under a transversal magnetic field is a simple yet effective method to homogenise the temperature and composition distributions, which can be used to control the primary phase and the distribution of iron-rich intermetallics during solidification.

The Effect of EndoAnchors on Aneurysm Sac Regression for Patients Treated With Infrarenal Endovascular Repair With Hostile Neck Anatomies: A Propensity Scored Analysis

Purpose: To analyze sac evolution patterns in matched patients with hostile neck anatomy (HNA) treated with standard endovascular aneurysm repair (sEVAR) and endosutured aneurysm repair (ESAR). Methods: Observational retrospective study using prospectively collected data between June 2010 and December 2019. ESAR group data were extracted from the primary arm of the PERU registry with an assigned identifier (NCT04100499) at 8 centers and those from the sEVAR came from 4 centers. Suitability for inclusion required: no proximal endograft adjuncts (besides EndoAnchor use), ≤15 mm neck length and minimum of 12-months follow-up imaging. Bubble-shaped neck (noncylindrical short neck with discontinuous seal) aspect was analyzed. Both groups were analyzed using propensity score matching (PSM) for aortic neck length, width, angulation, and device fixation type. Main outcome assessed was sac evolution patterns (sac expansion and regression were defined as >5mm increase or decrease, of the maximum sac diameter respectively; all AAAs within this ±5 mm range in diameter change were considered stable) and secondary outcomes were type-Ia endoleaks; other endoleaks and mortality. A power analysis calculation >80% was confirmed for sac regression evaluation. Results: After exclusions, PSM resulted in 96 ESAR and 96 sEVAR patients. Mean imaging follow-up (months) was 44.4±21.3 versus 43.0±19.6 (p=0.643), respectively. The overall number of patients achieving sac regression was higher in the ESAR group (n=57, 59.4% vs n=31, 32.3%; p<0.001) and the cumulative sac regression achieved at 5 years was 65% versus 38% (p=0.003) in favor of the ESAR group. There were no statistically significant differences in type-Ia endoleak and/or other endoleaks. Univariate analysis for sac regression patients in the sEVAR and ESAR group individually showed the bubble-shape neck as a predictor of sac regression failure. There were no statistical differences in overall and aneurysm-related mortality. Conclusion: Endosutured aneurysm repair provided improved rates of sac regression for patients with AAA and HNA when compared with sEVAR at midterm and up to 5 years, despite similar rates of type-Ia endoleaks, and the need to consider some important limitations. The presence of bubble-shaped neck was a predictor of sac regression failure for both groups equally. Clinical Impact The use of EndoAnchors aids and improves EVAR treatment in hostile neck anatomies by an increased rate of sac regression when compared to EVAR treatment alone in up to 5 year analysis. Moreover, a trend to reduced number of type Ia endoleaks is also achieved, although not significant in the present study. This data, adds to current and growing evidence on the usefulness of EndoAnchors for AAA endovascular treatment.

Outer surface lipoproteins from the Lyme disease spirochete exploit the molecular switch mechanism of the complement protease C1s

Proteolytic cascades comprise several important physiological systems, including a primary arm of innate immunity called the complement cascade. To safeguard against complement-mediated attack, the etiologic agent of Lyme disease, Borreliella burgdorferi, produces numerous outer surface-localized lipoproteins that contribute to successful complement evasion. Recently, we discovered a pair of B.burgdorferi surface lipoproteins of the OspEF-related protein family-termed ElpB and ElpQ-that inhibit antibody-mediated complement activation. In this study, we investigate the molecular mechanism of ElpB and ElpQ complement inhibition using an array of biochemical and biophysical approaches. Invitro assays of complement activation show that an independently folded homologous C-terminal domain of each Elp protein maintains full complement inhibitory activity and selectively inhibits the classical pathway. Using binding assays and complement component C1s enzyme assays, we show that binding of Elp proteins to activated C1s blocks complement component C4 cleavage by competing with C1s-C4 binding without occluding the active site. C1s-mediated C4 cleavage is dependent on activation-induced binding sites, termed exosites. To test whether these exosites are involved in Elp-C1s binding, we performed site-directed mutagenesis, which showed that ElpB and ElpQ binding require C1s residues in the anion-binding exosite located on the serine protease domain of C1s. Based on these results, we propose a model whereby ElpB and ElpQ exploit activation-induced conformational changes that are normally important for C1s-mediated C4 cleavage. Our study expands the known complement evasion mechanisms of microbial pathogens and reveals a novel molecular mechanism for selective C1s inhibition by Lyme disease spirochetes.

Influence of growth velocity on fragmentation during directional solidification of Al – 14 wt.% Sn alloy studied by in-situ synchrotron X-radiography

Directional solidification of Al – 14 wt.% Sn alloy was investigated by means of synchrotron X-radiography at the European Synchrotron Radiation Facility (ESRF). The dynamics of the solidification microstructure formation was studied in-situ and in real-time. In the present manuscript, a special attention is given to the influence of increasing growth velocity on the fragmentation phenomenon of dendrite arms, which has an important role and impact on the final grain structure. Fragmentations of both secondary dendrite arms and more strikingly part of primary trunks have been observed. The experiments show that the number of fragments increases concomitantly with the solidification growth rate until it reaches a limit value after which fewer or no more fragments are observed. The possible origins of the fragmentation are discussed in detail and the likelihood of each of these potential mechanisms is estimated to understand the reason of both primary and secondary arm detachment. It is shown that the fragmentation in a transient regime is correlated to the variations of the solute accumulation, latent heat rejection and the curvature of the attachment neck during solidification. Moreover, during these experiments, Columnar-to-Equiaxed Transition (CET) induced by the fragmentation phenomenon is observed. The velocity of the dendrite fragments due to the buoyancy force is a major parameter to control the CET and our results show that a reverse Equiaxed-to- Columnar Transition can even be observed. Once the growth velocity is of the same order or higher than the fragment flotation velocity, the fragments are trapped within the columnar dendritic microstructure, and CET cannot take place or the equiaxed regime cannot be sustained.

New-targeted therapy for leukemia based on Endoplasmic Reticulum Stress

The unfolded protein response (UPR) is an evolutionarily conserved adaptive pathway, which is activated by the stress of the endoplasmic reticulum (ER). ER stress often occurs due to the high protein demand in cells and protein folding errors in several diseases, such as different cancers and autoimmune diseases. UPR is mediated by three primary arms called inositol-requiring enzyme-1α (IRE1α), protein kinase RNA-like endoplasmic reticulum kinase (PERK), and activating transcription factor 6α (ATF6α). Given that homeostasis in protein synthesis is frequently deregulated in cancers, UPR plays a critical role in controlling survival and cell death. In addition,, resistance to apoptosis is mediated by the pro-survival mechanism of ER stress in cancer cells. Recent evidence highlighted the deregulation of UPR signaling in hematopoietic stem cells (HSCs) and leukemic cells, so that targeting UPR-driven pro-survival pathways may present new therapeutic benefits in leukemia. In this review article, we aim to provide an updated knowledge on the role of UPR as a novel therapeutic target in leukemia. We first define the different types of leukemia and their challenges with current treatments, and then explore the contribution of UPR to leukemia pathogenesis and treatment. Finally, UPR targeting strategies in pre-clinical and clinical trials of patients with leukemia will be presented.

Microstructure evolution of Inconel 625 alloy during single-track Laser Powder Bed Fusion

Elemental microsegregation and precipitate formation are inevitable during solidification of Additive Manufacturing (AM) parts. In this study, single-track Laser Powder Bed Fusion (LPBF) has been combined with optical and electron microscopy, as well as thermodynamic (CALPHAD) simulations, to evaluate the solidified microstructure and also the formation of the precipitates in an as-built LPBF microstructure of Inconel625 (IN625). It is shown that the microstructure consists mainly of columnar Nickel–Chromium ( γ -FCC) cell-like dendrites which grew epitaxially from the substrate. Utilizing Scanning Transmission Electron Microscopy (STEM) with Energy-Dispersive X-ray Spectroscopy (EDS) and High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy (HAADF-STEM), we have detected NbC, γ ′ ′ -Ni 3 Nb, and laves precipitates embedded into the interdendritic regions. The level of microsegregation and the microsegregation patterns during the solidification of primary arms are obtained by STEM-EDS, and calculated using the Scheil–Gulliver (with solute trapping) and DIffusion-Controlled TRAnsformations (DICTRA) methods. Good agreement is seen between the Scheil–Gulliver predictions and STEM-EDS observations of microsegregation, however the level of elemental microsegregation was overestimated in DICTRA simulations as compared to the experimental result. The formation of precipitates was also evaluated computationally by calculation of driving force for the nucleation of the precipitates from the last solidified liquid where the composition and thermal information for the last solidified liquid extracted from the Scheil solidification simulation. The precipitates predicted via CALPHAD were compared with the precipitates identified via HAADF-STEM analysis inside the interdendritic region.

Parallel-GPU AMR implementation for phase-field lattice Boltzmann simulation of a settling dendrite

The motion of the equiaxed grains plays an important role in macrosegregation. To simulate the motion of three-dimensional (3D) equiaxed dendrites growing in an undercooled melt, a large computational domain with small grids is required. In this study, we investigated the morphology and velocity of the settling dendrite and the growth velocity of its primary arms by implementing parallel computing with multiple graphics processing units (GPUs) for the adaptive mesh refinement (AMR) method (parallel-GPU AMR). A multiple-grid (MG) method that assigns different grid sizes to each field was also applied to the parallel-GPU AMR. A large-scale phase-field lattice Boltzmann (PF-LB) parallel-GPU AMR simulation of the settling dendrite was performed. The parallel GPU AMR method developed for the 3D PF-LB solidification model can evaluate the growth and motion of 3D equiaxed dendrite settling in an undercooled melt. The results are achieved with a significant acceleration of the 3D PF-LB simulations of settling dendrite and using a significantly reduced number of GPUs required for the simulation.

Advanced Bronchogenic Carcinoma with Secondary Liver Metastasis and Sepsis as an Initial Hospital Presentation; The Shortcomings of Preventive Care Medicine in Nigeria

Chronic diseases are the most prevalent worldwide. Evidence-based medicine points to primary care as the most effective tool to minimize the burden through primary prevention and early detection of diseases. In keeping with this, the primary care arm of medicine can be regarded as the gatekeeper of public health. The rising incidence of chronic diseases indicates that the primary care system may fail to live up to its responsibility. We present a case of an elderly male who came to the hospital with advanced bronchogenic carcinoma, secondary liver metastasis, and sepsis. He presented for the first time in over a year since he started experiencing symptoms. He had no contact with his primary care physicians, nor was he vaccinated against the influenza virus or the coronavirus.

The heterogeneous band microstructure and mechanical performance in a wire + arc additively manufactured 2219 Al alloy

In this study, a 2219 Al alloy with a heterogeneous band structure characterized by an alternating distribution of equiaxed and columnar α-Al grains was obtained by wire + arc additive manufacturing. The volume fractions of the equiaxed and columnar grains were varied by adjusting the cooling mode of the substrate. The volume fraction of the columnar grains in a water-cooled (WC) deposit was approximately 16% higher than that in an air-cooled (AC) deposit. Moreover, the WC deposit exhibited smaller primary arm dendrite spacing and lower porosity than those of the AC deposit. The results of in-situ tensile testing revealed that the columnar grains could coordinate and distribute strain more effectively than the equiaxed grains. The ex-situ electron back scatter diffraction data showed that the observed deformations of the columnar and equiaxed grains during tensile testing were non-uniform and non-synchronization. Furthermore, numerous dislocations in the columnar grains of the deposit coordinated the deformation process. According to tensile testing data, the ultimate strength, yield strength, and elongation of the WC deposit were 247.7 ± 17.7 MPa, 110.1 ± 6.3 MPa and 11.9 ± 0.7%, which were higher than those of the AC deposit by 10.76%, 15.78%, and 26.78%, respectively. Therefore, the heterogeneous band structure of the equiaxed and columnar grains ensured good synergy between strength and ductility.