EM

Decentralized EM Algorithm for Gaussian Mixtures under Data Heterogeneity and Partial Labeling

arXiv:2411.05591v2 Announce Type: replace-cross Abstract: We systematically study several network-based Expectation-Maximization (EM) algorithms for the Gaussian mixture model within decentralized federated learning (DFL). Our theoretical investigation shows that directly extending the classic EM algorithm to DFL leads to a biased estimator when data are heterogeneously distributed across sites. To address this, we introduce a momentum network EM (MNEM) algorithm, which integrates...

Direct Detection and Atomic Modeling of Ligands in Cryo-EM Maps Using Deep Learning

Cryogenic electron microscopy (cryo-EM) has become an increasingly important for structure-based drug discovery by enabling characterization of interactions between macromolecules and small-molecule ligands. However, computational interpretation of ligand density remains challenging, particularly when ligand locations are unknown or local map resolution is limited. Existing methods generally require well-resolved macromolecular structures and predefined binding sites, limiting their...

Two Datasets Are Better Than One: Method of Double Moments for 3-D Reconstruction in Cryo-EM

Announce Type: replace Abstract: Cryo-electron microscopy (cryo-EM) is a powerful imaging technique for reconstructing three-dimensional molecular structures from noisy tomographic projection images of randomly oriented particles. We introduce a new data fusion framework, termed the method of double moments (MoDM), which reconstructs molecular structures from two instances of the second-order moment of projection images obtained under distinct orientation distributions: one uniform, the...

'Bring 'em on': Delta wants United's crown over the Pacific, too

RIO DE JANEIRO — Delta Air Lines is the nation's most profitable carrier, but its hungry rival, United Airlines, is far bigger over the Pacific. Delta's new president, Peter Carter, says that just won't stand. "We want to become stronger, better, faster in the trans-Pacific, and we want to become the leading U.S. carrier" across the Pacific, Carter told CNBC in an interview here during the International Air Transport Association's annual meeting.

Cryo-EM provides insight into how the Staphylococcus aureus IsdH receptor removes hemin from the hemoglobin:haptoglobin complex

Staphylococcus aureus extracts hemin from human hemoglobin (Hb) to overcome host-imposed iron limitation. How it recovers Hb-bound hemin from the hemoglobin:haptoglobin (Hb:Hp) complex, the major circulating form of Hb outside red blood cells, remains unclear. Here we use cryo-electron microscopy, biophysical measurements, and solution kinetics to define how the S. aureus IsdH surface receptor extracts hemin from Hb:Hp.

EM Currencies Advance on Iran Talks With Rand Leading Gains

An employee counts South African rand banknotes at a currency exchange office in Pretoria. Photographer: Waldo Swiegers/Bloomberg

EM Long Bonds Seen Missing Out on Any Iran Peace Dividend

Light trails left by passing traffic at night in Daegu, South Korea, on Tuesday, April 23, 2024. Gross domestic product advanced 1.3% in the three months through March versus the previous quarter, the Bank of Korea said Thursday, an advance that soundly outpaced economists’ consensus for a 0.6% expansion.

Geometric shape matching for recovering protein conformations from single-particle Cryo-EM data

Announce Type: replace-cross Abstract: We address recovery of the three-dimensional backbone structure of single polypeptide proteins from single-particle cryo-electron microscopy (Cryo-SPA) data. Cryo-SPA produces noisy tomographic projections of electrostatic potentials of macromolecules. From these projections, we use methods from shape analysis to recover the three-dimensional backbone structure.

EM’s Record Rally Leads Two Hedge Funds to Turn Away Investors

EM Stocks Hit Record High on AI, Currencies Lower as Oil Climbs

South Korea’s Kospi index marked a record high.