GradDFT. A software library for machine learning enhanced density functional theory.

Density functional theory (DFT) stands as a cornerstone method in computational quantum chemistry and materials science due to its remarkable versatility and scalability. Yet, it suffers from limitations in accuracy, particularly when dealing with strongly correlated systems. To address these shortcomings, recent work has begun to explore how machine learning can expand the capabilities of DFT: an endeavor with many open questions and technical challenges. In this work, we present GradDFT a fully differentiable JAX-based DFT library, enabling quick prototyping and experimentation with machine learning-enhanced exchange-correlation energy functionals. GradDFT employs a pioneering parametrization of exchange-correlation functionals constructed using a weighted sum of energy densities, where the weights are determined using neural networks. Moreover, GradDFT encompasses a comprehensive suite of auxiliary functions, notably featuring a just-in-time compilable and fully differentiable self-consistent iterative procedure. To support training and benchmarking efforts, we additionally compile a curated dataset of experimental dissociation energies of dimers, half of which contain transition metal atoms characterized by strong electronic correlations. The software library is tested against experimental results to study the generalization capabilities of a neural functional across potential energy surfaces and atomic species, as well as the effect of training data noise on the resulting model accuracy.

PSON: A Serialization Format for IoT Sensor Networks.

In many Internet of Things (IoT) environments, the lifetime of a sensor is linked to its power supply. Sensor devices capture external information and transmit it. They also receive messages with control commands, which means that one of the largest computational overheads of sensor devices is spent on data serialization and deserialization tasks, as well as data transmission. The simpler the serialization/deserialization and the smaller the size of the information to be transmitted, the longer the lifetime of the sensor device and, consequently, the longer the service life. This paper presents a new serialization format (PSON) for these environments, which simplifies the serialization/deserialization tasks and minimizes the messages to be sent/received. The paper presents evaluation results with the most popular serialization formats, demonstrating the improvement obtained with the new PSON format.

Acute calciphylaxis precipitated by the initiation of hemodialysis.

Calciphylaxis, or calcific uremic arteriopathy (CUA), is characterized by metastatic calcification in the media of small arteries and arterioles leading to cutaneous necrosis. It is most commonly seen in patients with end stage renal disease who have elevated serum calcium × phosphorus (Ca × P) product. Normalization of Ca × P product is considered paramount in the prevention and treatment of CUA. We describe a novel presentation of CUA in which a Stage-5 CKD patient developed signs and symptoms of CUA immediately after initiation of hemodialysis (HD). We postulate that an influx of calcium from the dialysate into the patient's blood, in addition to correction of her acidosis, led to abundant substrate in a favorable milieu for Ca-P complex formation at the time of her first HD session. Our case is the first reported case of HD associated iatrogenic acute CUA. To avoid this complication, we should maintain adequate hydration,use lower calcium dialysate, and avoid vitamin D analogues and calcium-containing medications when initiating HD in patients with high Ca-P product. Since sodium thiosulfate is known to prevent precipitation of Ca-P complexes, its empiric use during initial HD treatments may be effective in preventing CUA, a potentially fatal disease.

Diffuse alveolar haemorrhage in ANCA-negative pauci-immune crescentic glomerulonephritis.

Pulmonary renal syndrome (PRS) is a combination of diffuse pulmonary haemorrhage and glomerulonephritis (GN). Though an established form of presentation in anti-neutrophil cytoplasmic autoantibody (ANCA)-associated GN and vasculitis, diffuse pulmonary haemorrhage is extremely unusual in those with ANCA-negative GN. We present here a case of a 76-year-old Hispanic female with stage IV chronic kidney disease (serum creatinine of 2 mg/dL), who presented with diffuse alveolar haemorrhage and nephritic syndrome. Less than 1 week prior to the full-blown PRS, she was treated for an apparent pneumonia as was evidenced by a right lower lobe infiltrate on her chest X-ray. Retrospectively, this was likely a focal pulmonary haemorrhage. ANCA were persistently negative, and the remainder of her immunologic workup was normal. Renal biopsy was diagnostic of crescentic pauci-immune GN. The patient required a ventilator and haemodialysis support (serum creatinine 6 mg/dL), and was successfully treated with methylprednisolone, cyclophosphamide and a total of six cycles of plasmapheresis. Once her oliguria resolved, the creatinine plateaued at 2.7 mg/dL. Our case illustrates that diffuse alveolar haemorrhage can be a distinct clinical feature even in patients with ANCA-negative pauci-immune crescentic glomerulonephritis.

Bilateral idiopathic trochleitis as a cause of frontal cephalgia.

Trochleitis is defined as the inflammation of the trochlea and peri-trochlear region, in particular the sheath of the superior oblique muscle; being bilateral is an extremely rare event. We think that is important to bear in mind for physicians as a remote possibility in ruling out causes of headache.

Nosocomial valve endocarditis due to corynebacterium striatum: a case report.

Staphylococcus aureus, Coagulase-negative staphylococci, and Enterococci sp. are the usual pathogens involved in nosocomial bacterial endocarditis. Corynebacterium species isolation in blood specimens is usually considered to be a contaminant. We present an interesting case of native mitral valve endocarditis in a 73 year old African American female that was diagnosed days after she was discharged from our institution. The infection was cleared with medical therapy alone.

Over a millon Creatine Kinase due to a heavy work-out: A case report.

Rhabdomyolysis induced by exercise is a very well known entity, several cases has been reported in the literature related with strenuous activities, weight lifting, marathon running, overexertion in an untrained person, knee bends, etc. We reported an interesting case of exercise-induced rhabdomyolysis in a 25 year old Hispanic male, after resuming his regular physical activity, with the highest creatine kinase described in the literature, successfully treated with aggressive hydration only and no complications.

Superior sagittal sinus thrombosis and bilateral sixth-nerve palsy in a child with nephrotic syndrome.

We report on a patient with nephrotic syndrome who developed superior sagittal sinus thrombosis. He presented with double vision due to bilateral sixth-nerve palsy and papilledema. The thrombosis resolved with intravenous heparin and oral corticosteroids. A month later there were no signs of ocular movement paresis, and both optic nerves were normal.