Things to Do in L.A. Tap to enable a layout that focuses on the article. Teachers, union members, attend a rally at Molina Grand Park in Los Angeles on Wednesday. United Teachers Los Angeles and Local 99 service workers announced members would strike on April 14, if no deal is reached before then. This is read by an automated voice. Please report any issues or inconsistencies here .

Things to Do in L.A. Tap to enable a layout that focuses on the article. L.A. teachers union widely expected to announce strike date at massive Wednesday rally Members of the largest unions representing teachers and nonteachers participate in joint rally at Grand Park in March 2023. The scene will be repeated on Wednesday, with union members once again on the verge of a strike. This is read by an automated voice. Please report any issues or inconsistencies here .

Things to Do in L.A. Tap to enable a layout that focuses on the article. Supporters of the Green Dot charter at Locke High intently watch the debate over the school's future. On Tuesday, the board narrowly voted to close the school at the end of the year. This is read by an automated voice. Please report any issues or inconsistencies here .

Things to Do in L.A. Tap to enable a layout that focuses on the article. This is read by an automated voice. Please report any issues or inconsistencies here . Alberto Carvalho issued his first statement after an FBI raid on his home and office. The investigation is linked to AllHere, the company behind a failed multimillion-dollar chatbot initiative that the district launched with fanfare in 2024 but that failed within months.

The head of an education technology startup that created a highly touted chatbot for the Los Angeles school system has been arrested and charged with fraud. Federal prosecutors, in an indictment unsealed Tuesday, accused Joanna Smith-Griffin of defrauding investors and charged her with securities fraud, wire fraud and aggravated identity theft. Smith-Griffin, 33, is the founder and former chief executive of AllHere, the Boston-based company that created "Ed," an artificial-intelligence tool billed as revolutionary for students' education and the interaction between the L.A. Unified School District and the families it serves. After unveiling the chatbot with great fanfare in March, L.A. school officials, months later, quietly disconnected the tool -- which was supposed to respond to any question from students or parents in an accurate, helpful and private manner. LAUSD board members at Tuesday's meeting will consider resolutions on immigration sanctuary, LGBTQ protection and accelerating the teaching of current events.

MRI-targeted biopsy has shown significant advantages over conventional random sextant biopsy, detecting more clinically significant cancers and improving risk stratification. However, needle targeting accuracy, especially in transperineal MRI-guided biopsies, presents a challenge due to needle deflection. This can negatively impact patient outcomes, leading to repeated sampling and inaccurate diagnoses if cancerous tissue isn't properly collected. To address this, we developed a novel differential drive prototype designed to improve needle control and targeting precision. This system, featuring a 2-degree-of-freedom (2-DOF) MRI-compatible cooperative needle driver, distances the robot from the MRI imaging area, minimizing image artifacts and distortions. By using two motors for simultaneous needle insertion and rotation without relative movement, the design reduces MRI interference. In this work, we introduced two mechanical differential drive designs: the ball screw/spline and lead screw/bushing types, and explored both hollow-type and side-pulley differentials. Validation through low-resolution rapid-prototyping demonstrated the feasibility of differential drives in prostate biopsies, with the custom hollow-type hybrid ultrasonic motor (USM) achieving a rotary speed of 75 rpm. The side-pulley differential further increased the speed to 168 rpm, ideal for needle rotation applications. Accuracy assessments showed minimal errors in both insertion and rotation motions, indicating that this proof-of-concept design holds great promise for further development. Ultimately, the differential drive offers a promising solution to the critical issue of needle targeting accuracy in MRI-guided prostate biopsies.

Intra-operative image guidance using magnetic resonance imaging (MRI) can significantly enhance the precision of surgical procedures, such as deep brain tumor ablation. However, the powerful magnetic fields and limited space within an MRI scanner require the use of robotic devices to aid surgeons. Piezoelectric motors are commonly utilized to drive these robots, with piezoelectric ultrasonic motors being particularly notable. These motors consist of a piezoelectric ring stator that is bonded to a rotor through frictional coupling. When the stator is excited at specific frequencies, it generates distinctive mode shapes with surface waves that exhibit both in-plane and out-of-plane displacement, leading to the rotation of the rotor. In this study, we continue our previous work and refine the motor design and performance, we combine finite element modeling (FEM) with stroboscopic and time-averaged digital holography to validate a further plastic-based ultrasonic motor with better rotary performance.

In a step forward from pandemic-era learning setbacks, standardized test scores in the Los Angeles school system made gains in all tested grade levels in math and English, Supt. Alberto Carvalho announced on Tuesday, although a majority of students remain below the state's grade level standards. At this time, the L.A. results can't be evaluated in a broader context because the California Department of Education has not publicly released statewide scores from the 2024 spring semester testing. Yet the scores suggest Los Angeles students have begun rebounding from sharp pandemic lows, when campuses were closed for more than a year and students kept pace as best they could through remote learning. In English, districtwide proficiency increased from about 41% to 43% of students year over year.

Alberto Carvalho, who remains determined to bring artificial intelligence into district classrooms despite the collapse of the technology company leading the effort, will appoint a task force to examine what went wrong and how to move forward. The schools chief announced the task force in an interview with The Times in advance of Tuesday's annual address to administrators, which is akin to a state-of-the-schools speech. In his public address, Carvalho is expected to highlight academic progress and L.A. Unified School District initiatives. In a recent appearance, he said he was hopeful that standardized test scores would rise at all grade levels in math and English. Although school districts throughout the state have received results -- and can make them public if they wish -- the state has not yet released local or statewide scores.

Alberto Carvalho said he is moving foward with his venture into artificial intelligence -- a platform designed to help students and families navigate the complexities of the district -- despite the collapse of the company that designed an AI chatbot. In his first extended interview about what happened, the L.A. schools chief described a fully functional AI-driven platform that is in place and owned by the district -- with everything but a chatbot for now. But parents and teachers are questioning this characterization, because the platform is not available across the school system and its signature feature is sidelined. They said they have no idea how or how well it works, how to access it or what it is supposed to do. Their only information, they said, came from splashy media events.