3D Technology Laboratories (United States)

Learning involves forming associations between sensory events that have a consistent temporal relationship. Influential theories based on prediction errors explain numerous behavioral and neurobiological observations but do not account for how animals measure the passage of time. Here, we propose a theory for temporal causal learning, where the structure of inter-stimulus intervals is used to infer the singular cause of a rewarding stimulus. We show that a single assumption of timescale invariance, formulated as an hierarchical generative model, is sufficient to explain a puzzling set of learning phenomena, including the power-law dependence of acquisition on inter-trial intervals and timescale invariance in response profiles. A biologically plausible algorithm for inference recapitulates salient aspects of both timing and prediction error theories. The theory predicts neural signals with distinct dynamics that encode causal associations and temporal structure.

BackgroundVaginitis is a major cause of healthcare visits in the US, costing over $1.2 billion annually. Point-of-care (POC) nucleic acid amplification tests (NAATs) could improve accuracy of diagnosis and treatment during initial visit for vaginitis compared to send-out NAATs.MethodsA secondary analysis of data was collected from test operators at POC testing sites where the Xpert Xpress Multiplex Vaginal Panel test (“MVP test”) was performed. Users completed a survey assessing their experience with the instrument system and the PCR-based MVP test. ResultsThe MVP test demonstrated consistent performance, measured by positive and negative percent agreement, across all user categories, including both trained and untrained staff. Performance was evaluated based on job function (clinicians, non-clinicians, support staff) and educational level (bachelor’s degree or higher, associate’s degree or some college, high school diploma/general educational development (GED) with technical certification), with no significant differences in performance (P >0.082 and P >0.050, respectively).User feedback from 19 operators showed that 15/19 (79%) of users found the GeneXpert Xpress Instrument System easy to set up, and 18/19 (96%) found the test instructions easy to follow. Users described the system as user-friendly with clear instructions and helpful videos. Overall, 19/19 (100%) agreed that the MVP test was easy to perform.ConclusionsAvailability of accurate POC diagnostics will only be useful if the test can be performed by any potential user. Our study results suggest that the MVP test was acceptable to users and that results were accurate regardless of user qualifications. Thus, this test has the potential to improve the immediate clinical outcome by supporting accurate, same day treatment for causes of vaginitis.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12879-025-11304-8.

The escalating data volume and complexity resulting from the rapid expansion of artificial intelligence (AI), Internet of Things (IoT), and 5G/6G mobile networks is creating an urgent need for energy-efficient, scalable computing hardware. Here, we demonstrate a hypermultiplexed tensor optical processor that can perform trillions of operations per second using space-time-wavelength three-dimensional optical parallelism, enabling O(N2) operations per clock cycle with O(N) modulator devices. The system is built with wafer-fabricated III/V micrometer-scale lasers and high-speed thin-film lithium niobate electro-optics for encoding at tens of femtojoules per symbol. Lasing threshold incorporates analog inline rectifier (ReLU) nonlinearity for low-latency activation. The system scalability is verified with machine learning models of 405,000 parameters. A combination of high clock rates, energy-efficient processing, and programmability unlocks the potential of light for low-energy AI accelerators for applications ranging from training of large AI models to real-time decision-making in edge deployment.

Human papillomavirus (HPV) testing is highly sensitive compared to cytology, with the trade‐off of being less specific. We investigated whether select combinations of HPV genotypes, ascertained by Linear Array (LA) and Xpert HPV (GX), can optimize sensitivity/specificity trade‐offs to detect high‐grade cervical intraepithelial neoplasia (CIN2+). In a study in Cape Town, South Africa, 586 women living without and 535 living with HIV, aged 30‐65 years, were recruited. Each woman underwent a pelvic exam to collect cervical samples (tested by LA and GX for 14 high‐risk HPV genotypes) and underwent colposcopy with histological sampling to determine CIN2+. In multivariable logistic regression of LA results, only HPV genotypes 16, 18, 31, 33, 35, 52, 58 were significantly associated with CIN2+ (P < .05). Xpert includes these seven types along with HPV 45 within three of the test's five channels and we defined these eight types as restricted genotyping (ie 16, 18, 31, 33, 35, 45, 52, 58). Full genotyping was defined as all 14 high‐risk types. Sensitivity estimates for full genotyping using LA were similar to that of restricted genotyping: 83.9% (full) vs 79.0% (restricted) in women without HIV and 93.0% (full) vs 88.9% (restricted) in women living with HIV. Specificity estimates improved for restricted vs full genotyping: 87.4% (full) vs 90.8% (restricted) in women without HIV and 63.7% (full) vs 71.4% (restricted) in women living with HIV. To optimize the performance of HPV testing for cervical cancer screening in high‐burden, under‐resourced settings like South Africa, only HPV 16, 18, 31, 33, 35, 45, 52, 58 could be included to define screen‐positive. We recommend the inclusion of HPV45 for its known link to adenocarcinoma.

Nearly all 3-D data sets that I see are badly aliased, which wreaks havoc on the data quality. But there is a simple solution.

Abstract— The crack tip cyclic heat generation rate, fatigue crack growth rate, and the crack closure stress were measured in a β‐annealed Ti‐6Al‐4V for R ratios of ‐0.1, 0.1 and 0.2. The R= ‐0.1 and 0.1 cases exhibited macroscopic crack closure and the R = 0.2 case exhibited no macroscopic crack closure as measured by strain gage techniques. There was a transition in the slope of the da/dN vs ΔK curve for the closure cases and no transition for the no‐closure case. The crack tip heat generation rate above the transition for the closure cases was an order of magnitude greater than for the no‐closure case. Also the crack tip heat generation rate below the transition was greater for the closure cases than for the no‐closure case. The transition in the heat generation rate and the crack growth rate was attributed to a transition from static frictional locking of shear branch cracks to sliding of the branch crack surfaces. Below the transition the crack faces are locked open creating a large roughness‐induced closure component. When the branch cracks are allowed to undergo reverse shear, the amount of roughness‐induced closure markedly decreases and the fracture surface becomes less tortuous. The relative sliding generates the increased heat.

A new classification scheme for robotic force control algorithms is presented. It is shown that algorithms can be categorized according to whether they are joint-based or cartesian-based. Further, they can be grouped according to whether the innermost servo loop is based on torque, velocity, or position. For useful force control, closing an inner loop on position can greatly increase disturbance rejection while also allowing for a split rate servo controller to minimize the computational burden. Experimental results from the implementation of a new force feedback method are presented. This cartesian-based method uses an inner loop closed on position and has been implemented on an AdeptOne robot. Bias force application, force searching, and selective compliance about a synthetic remote center compliance (RCC) have all been implemented. Excellent results in free space and in hard contact have been achieved. This technique has been successfully used to assemble parts having 0.001 inch clearances.

A technical paper presented in this Journal in 1975 discussed the interior illumination of the flight deck of the Space Shuttle Orbiter. Almost two years later, August 12, 1977, millions of people witnessed the first Orbiter—named Enterprise—make its first free-flight landing. In those two years the development and design of other Orbiter illumination subsystems has progressed to final design configurations. The authors propose to extend the discussion of interior illumination to cover floodlighting of the lower center control console on the flight deck, lighting of the living quarters of the crew, and illumination of the airlock module. The harsh, hostile, space ambient conditions external to the Orbiter will be discussed in detail to establish the special requirements placed on designs of external lighting systems such as the overhead docking floodlight, floodlights attached to remotely-controlled manipulator arms used to move cargo, and floodlights located in the cargo bay. Finally, a brief description...