Accelerating the discovery of novel magnetic materials using machine learning-guided adaptive feedback.

Magnetic materials are essential for energy generation and information devices, and they play an important role in advanced technologies and green energy economies. Currently, the most widely used magnets contain rare earth (RE) elements. An outstanding challenge of notable scientific interest is the discovery and synthesis of novel magnetic materials without RE elements that meet the performance and cost goals for advanced electromagnetic devices. Here, we report our discovery and synthesis of an RE-free magnetic compound, Fe3CoB2, through an efficient feedback framework by integrating machine learning (ML), an adaptive genetic algorithm, first-principles calculations, and experimental synthesis. Magnetic measurements show that Fe3CoB2 exhibits a high magnetic anisotropy (K1 = 1.2 MJ/m3) and saturation magnetic polarization (Js = 1.39 T), which is suitable for RE-free permanent-magnet applications. Our ML-guided approach presents a promising paradigm for efficient materials design and discovery and can also be applied to the search for other functional materials.

Light and COP1 regulate level of overexpressed DET1 protein.

de-etiolated 1 (det1) and constitutive photomorphogenic 1 (cop1) were initially identified as constitutively photomorphogenic Arabidopsis mutants, exhibiting light-grown phenotypes in the dark. Subsequently, both were shown to be components of Damaged DNA Binding protein 1 (DDB1)/CULLIN4-type complexes. Arabidopsis has two DDB1 homologues, DDB1A and DDB1B, and DDB1A mutants enhance det1 phenotypes. Here we examine ddb1a cop1 double mutants and find that ddb1a weakly enhances some cop1 phenotypes but not others, suggesting developmental regulation of COP1-DDB1A interaction. DET1 loss of function strongly enhances cop1 phenotypes. Here we show that MycDET1 overexpression also enhances cop1 phenotypes, thus MycDET1 overexpression in cop1 mutants also generates loss of function effects. Finally, the effect of the cop1 mutant background on the biochemical properties of MycDET1 was examined. MycDET1 levels were found to be lower in the dark than in the light and this difference required COP1. In summary, both DDB1A loss of function and MycDET1 overexpression enhance cop1 phenotypes, while cop1 mutants fail to exhibit light regulation of MycDET1 levels.

Preliminary results of Zenith Fenestrated abdominal aortic aneurysm endovascular grafts.

BACKGROUND: Patients with juxtarenal aortic aneurysms who are unfit for open repair may be considered for fenestrated endovascular repair (fenEVAR). We report our initial experience with fenEVAR. METHODS: We reviewed the data on all our patients receiving fenEVAR for juxtarenal aortic aneurysms. RESULTS: Eight patients, average age 75 years, underwent fenEVAR. Endografts were designed from details obtained from preoperative computed tomography angiography. There were 6 grafts with superior mesenteric scallops and bilateral renal fenestrations, 1 with bilateral renal scallops, and 1 with a single renal fenestration. All patients survived 30 days. There was no renal failure requiring dialysis. At 10 weeks, 1 patient died from acute intestinal ischemia and multisystem organ failure, and another died from respiratory failure. CONCLUSIONS: It is feasible to offer fenEVAR to patients who are poor candidates for open repair. However, these procedures are technically challenging. Early outcomes are less favorable than other aortic endovascular procedures.

Endovascular repair of traumatic thoracic aortic tears.

BACKGROUND: Patients with thoracic aorta injuries (TAI) present a unique challenge. The purpose of this study was to review the outcomes of thoracic endovascular aortic repair (TEVAR) in patients with TAI. METHODS: A retrospective chart review of all patients admitted for TEVAR for trauma was performed. RESULTS: In a 5-year period, 19 patients (6 women and 13 men; average age, 42 y) were admitted to our trauma center with TAI. Mechanism of injury was a motor vehicle crash in 12 patients, motorcycle crash in 2 patients, automobile-pedestrian accident in 2 patients, 1 fall, 1 crush injury, and 1 stab wound to the back. A thoracic endograft was used in 6 patients and proximal aortic cuffs were used in 13 patients (68%). One patient (5%) died. There were no strokes, myocardial infarctions, paraplegia, or renal failure. CONCLUSIONS: TEVAR for TAI appears to be a safe option for patients with multiple injuries. TEVAR in young patients is still controversial because long-term endograft behavior is unknown.

Asymptomatic pancreatic cysts: a decision analysis approach to observation versus resection.

OBJECTIVES: Pancreatic cysts are being found with increasing frequency. Although symptomatic cysts should be resected, what to do about asymptomatic cysts is less clear. The purpose of this study was to determine threshold values to choose resection over observation for a patient with an asymptomatic pancreatic cyst. METHODS: Decision analysis assesses the consequences of a decision based on occurrence probabilities. This decision analysis assessed 1 decision, to resect or observe a patient with an asymptomatic pancreatic cyst. The consequences for resection are operative mortality/no operative mortality, short-term morbidity of patients surviving the operation, benign/malignant cyst, and life expectancy after resection of malignant lesions. The probabilities are based on the extant literature. The age-specific life expectancy for benign cysts was considered the same as for the general age-specific population from the 2002 United States Life Table. Because the operative mortality, distribution of benign versus malignant cysts, and life expectancy after resection or observation for malignant cysts vary, sensitivity analysis was done to assess the threshold values of these factors when resection becomes favored over observation. RESULTS: The baseline decision analysis is based on the following assumptions: 30% of lesions are malignant, operative mortality rate is 3%, and the 5-year survival rate of resected malignant cysts is 50%. Varying on age, the risk of the cystic lesion being malignant to favor resection is greater than 11.6% to 15.5%, the operative mortality rate has to be less than 7.4% to 13.8%, and the life expectancy gain by resecting, rather than observing a malignant lesion, has to be greater than 3.49 to 5.38 years. CONCLUSIONS: The decision to resect must be based on the surgeon's operative mortality rate, the predicted operative mortality for the individual patient, the probability that the lesion is malignant, and the survival difference between resecting and observing malignant cystic lesions. Overall, for resection to be recommended, the physician must believe that the risk that the lesion is malignant is approximately 15% or greater, that the life expectancy gained from resection be approximately 5 years or greater, and that the surgeons' operative mortality rate be approximately 8% or less.