Search Results (13)

We propose a data-efficient framework for automating sowing operations by agricultural robots in densely mixed polyculture environments. This study addresses the challenge of enabling robots to identify suitable sowing positions with minimal labeled data by integrating image-based field sensing with expert agricultural knowledge. We collected 84 RGB-depth images from seven field sites, labeled by synecological farming practitioners of varying proficiency levels, and trained a regression model to estimate optimal sowing positions and seeding quantities. The model’s predictions were comparable to those of intermediate-to-advanced practitioners across diverse field conditions. To implement this estimation in practice, we mounted a Kinect v2 sensor on a robot arm and integrated its 3D spatial data with axis-specific movement control. We then applied a trajectory optimization algorithm based on the traveling salesman problem to generate efficient sowing paths. Simulated trials incorporating both computation and robotic control times showed that our method reduced sowing operation time by 51% compared to random planning. These findings highlight the potential of interpretable, low-data machine learning models for rapid adaptation to complex agroecological systems and demonstrate a practical approach to combining structured human expertise with sensor-based automation in biodiverse farming environments. Full article

Background/Objective: The Empty Spiracles Homeobox 2 (EMX2) gene is a homeobox transcription factor that is critical for the development of the central nervous system and genitourinary system during embryogenesis. EMX2 has been shown to regulate cellular differentiation, migration, and proliferation through its involvement in transcriptional control. Dysregulation of EMX2 expression has been implicated in various pathological conditions, including cancer, but the precise molecular mechanisms underlying EMX2 functions in cancer remain incompletely understood. In this study, we focus on the expression profile and the prognostic significance of EMX2 in esophageal squamous cell carcinoma (ESCC). Methods/Results: The expression levels of EMX2 in clinical ESCC samples varied and appeared to be lower than those in adjacent normal tissues. In addition, EMX2 expression was detected in some of the 20 ESCC cell lines but not in others and was correlated with 5-FU sensitivity. EMX2 expression in ESCC cell lines was strongly associated with colony formation capacity in soft agar, and EMX2 knockdown decreased colony formation. Enforced expression of EMX2 decreased the side population (SP) ratio in FACS analysis but increased colony formation in SP fractions. Although it is a preliminary experiment, xenograft in immunodeficient (NOD) scid mice suggested that the forced expression of EMX2 increased tumorigenic capacity in vivo. A Kaplan–Meyer analysis of patients from whom 20 ESCC cell lines or 18 ESCC tissue samples were obtained indicated that EMX2 expression was a poor prognostic marker. Conclusion: EMX2 has a unique function in ESCC stemness and its expression is the stamped marker of poor prognosis in ESCC patients. Full article

Near-infrared photoimmunotherapy (NIR-PIT) is a promising cancer treatment that uses near-infrared light to activate a conjugate of a monoclonal antibody (mAb) and a photoactivatable silica phthalocyanine dye (IRDye700DX: IR700). Unlike conventional photodynamic therapy (PDT), NIR-PIT selectively destroys targeted tumor cells while preserving the surrounding normal tissue and providing superior tissue penetration. Recently, NIR-PIT has been approved for the treatment of unresectable recurrent head and neck cancers in Japan. It induces highly selective cancer cell death; therefore, it is expected to be a new curative treatment option for various cancers, including brain tumors. In this review, we compare the principles of NIR-PIT and PDT and discuss the potential applications of NIR-PIT for brain tumors. We selected targetable proteins across various types of brain tumors and devised a strategy to effectively pass the mAb–IR700 conjugate through the blood–brain barrier (BBB), which is a significant challenge for NIR-PIT in treating brain tumors. Innovative approaches for delivering the mAb–IR700 conjugate across the BBB include exosomes, nanoparticle-based systems, and cell-penetrating peptides. Small-molecule compounds, such as affibodies, are anticipated to rapidly accumulate in tumors within intracranial models, and our preliminary experiments demonstrated rapid uptake. NIR-PIT also induces immunogenic cell death and activates the anti-tumor immune response. Overall, NIR-PIT is a promising approach for treating brain tumors. It has the potential to overcome the limitations of conventional therapies and offers new hope to patients with brain tumors. Full article

I3MT-3 (HMPSNE) has been identified as a selective inhibitor of the supersulfide-producing enzyme 3-MST. In this study, we found that I3MT-3 inhibits inflammatory responses, including the secretion of the pro-inflammatory cytokine interleukin-1β (IL-1β) and inflammatory cell death pyroptosis, induced by the activation of the inflammasomes composed of NLRP1, NLRP3, or AIM2. However, interestingly, the knockdown of 3-MST did not affect the activation of the inflammasomes, suggesting that the inhibitory effect of I3MT-3 on inflammasome activation is mediated by alternative ways rather than the inhibition of 3-MST. Interestingly, an in vitro caspase assay revealed that I3MT-3 directly inhibits caspase-1 activation, and molecular docking simulations raised the possibility that the pyrimidone ring in I3MT-3 stabilizes direct interaction of I3MT-3 with caspase-1. Taken together, our data suggest that I3MT-3 inhibits inflammasome activation by targeting caspase-1, and show I3MT-3 as a potent inhibitor of caspase-1. Full article

Objective: Osteoarthritis is linked to dementia, but no longitudinal studies have established this connection. This prospective cohort study from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS) aimed to determine if knee osteoarthritis (KOA) independently predicts dementia in adults aged 65 and above. Methods: Participants were classified by the Kellgren–Laurence scale into no/minimal KOA (grades 0 and I) and definitive KOA (grade II or higher). We analyzed dementia incidence from 2009 to 2015 using long-term care insurance data, adjusting for age, sex, vascular risks, depressive symptoms, and activity levels. Results: Out of 1089 participants (58.9% female, average age 72.5), 72.0% had definitive KOA. Dementia occurrence was significantly higher in the definitive group (8.4%) compared to the no/minimal group (3.0%) (p < 0.001). A log-rank test and Cox regression analysis confirmed these findings, showing an adjusted hazard ratio of 2.29 (confidence interval: 1.12–4.68) for dementia in those with definitive KOA. Conclusions: These results suggest that KOA is a significant risk factor for dementia, highlighting the importance of addressing contributing factors in KOA patients to potentially slow the progression of dementia. Full article

Background: In the diagnosis of lumbar spinal stenosis (LSS), finding stenosis with magnetic resonance imaging (MRI) does not always correlate with symptoms such as sciatica or intermittent claudication. We perform decompression surgery only for cases where the levels diagnosed from neurological findings are symptomatic, even if multiple stenoses are observed on MRI. The objective of this study was to examine the time course of asymptomatic stenosis in patients with LSS after they underwent decompression surgery for symptomatic stenosis. Materials and Methods: The participants in this study comprised 137 LSS patients who underwent single-level L4–5 decompression surgery from 2003 to 2013. The dural sac cross-sectional area at the L3–4 disc level was calculated based on preoperative MRI. A cross-sectional area less than 50 mm² was defined as stenosis. The patients were grouped, according to additional spinal stenosis at the L3–4 level, into a double group (16 cases) with L3–4 stenosis, and a single group (121 cases) without L3–4 stenosis. Incidences of new-onset symptoms originating from L3–4 and additional L3–4-level surgery were examined. Results: Five years after surgery, 98 cases (72%) completed follow-up. During follow-up, 2 of 12 patients in the double group (16.7%) and 9 of 86 patients in the single group (10.5%) presented with new-onset symptoms originating from L3–4, showing no significant difference between groups. Additional L3–4 surgery was performed for one patient (8.3%) in the double group and three patients (3.5%) in the single group; again, no significant difference was shown. Conclusion: Patients with asymptomatic L3–4 stenosis on preoperative MRI were not prone to develop new symptoms or need additional L3–4-level surgery within 5 years after surgery when compared to patients without preoperative L3–4 stenosis. These results indicate that prophylactic decompression for asymptomatic levels is unnecessary. Full article

Currently, an agricultural method called Synecoculture^TM has been receiving attention as a means for multiple crop production and recovering from environmental degradation; it helps in regreening the environment and establishing an augmented ecosystem with high biodiversity. In this method, several types of plants are grown densely, and their management relies mainly on manual labor, since conventional agricultural machines and robots cannot be applied in complex vegetation. To improve work efficiency and boost regreening by scaling-up Synecoculture, we developed a robot that can sow, prune, and harvest in dense and diverse vegetation that grows under solar panels, towards the achievement of compatibility between food and energy production on a large scale. We adopted a four-wheel mechanism with sufficient ability to move on uneven terrain, and a two orthogonal axes mechanism with adjusted tool positioning while performing management tasks. In the field experiment, the robot could move straight on shelving slopes and overcome obstacles, such as small steps and weeds, and succeeded in harvesting and weeding with human operation, using the tool maneuver mechanism based on the recognition of the field situation through camera image. Full article

Early diagnosis of degenerative cervical myelopathy (DCM) is desirable, as delayed treatment can cause irreversible spinal cord injury and subsequent activity of daily living (ADL) impairment. We attempted to develop a straightforward and accurate diagnostic tool for DCM by combining the grip and release test (GRT) and grip strength. As a pilot study, we measured the GRT and grip strength of patients with DCM (n = 247) and a control group (n = 721). Receiver operating characteristic analysis was performed using the lower left and right. The Youden index was used to set cutoff values by sex and age group. The diagnostic performance of each test varied by sex and age, and a diagnostic support tool was created to determine any abnormal results in a test. The calculated M/F cutoff values for GRT were as follows: 40–59 years, 21/18; 60–69 years, 17/17; 70–79 years, 15/15; and 80–89 years, 11/12. The calculated M/F cutoff values for grip strength 32/20, 29/13, 21/15, and 19/10. When either GRT or grip strength was judged as positive, the overall sensitivity was 88.2%, specificity was 78.1%, positive likelihood ratio was 4.03, and the negative likelihood ratio was 0.15. This novel diagnostic support tool was superior to using GRT and grip strength alone in the early DCM diagnosis. Future research to obtain age- and sex-specific data is necessary to validate and further improve the tool. Full article

Background: Lumbar spinal stenosis (LSS) is a clinical syndrome based on anatomic narrowing of the spinal canal. It is well known that anatomic narrowing of the spinal canal is essential for manifestation, but not all of them cause symptoms. There are many studies assessing the relationship between dural tube compression on MRI and clinical symptoms; however, most of them are cross-sectional. The purpose of this study was to reveal the magnitude of dural tube compression’s influence on the presence or development of LSS symptoms at the six-year follow-up and the occurrence of surgery during the follow-up period or not in the community setting. Methods: This was a longitudinal observational study of 459 participants who were assessed for typical LSS symptoms, and whose Roland–Morris Disability Questionnaire and numerical rating scale of leg pain and numbness was recorded using a questionnaire and conventional MRI of the lumbar spine. Typical LSS symptoms were judged using an LSS diagnostic support tool, which was a self-administered, self-reported history questionnaire (LSS-SSHQ). After six years, 232 subjects (follow-up rate 50.5%) were followed-up with typical LSS symptoms using LSS-SSHQ by mail. The relationship between the magnitude of dural tube compression evaluated by dural tube cross-sectional area (DCSA) in the initial assessment and the time course of typical LSS symptoms for the six-year duration were analyzed. In addition, predictors of the presence of typical LSS symptoms at the six-year follow-up were assessed. Furthermore, we investigated the relationship between typical LSS symptoms and DCSA during the initial assessment of patients who underwent surgery during the follow-up period. A multivariate logistic regression analysis was performed for statistical analysis. Results: (1) Severe dural tube compression did not show that LSS symptoms continued after six years. (2) Severe dural tube compression could not detect development of LSS-symptoms and surgery during the six-year period. Conclusion: Severe dural tube compression could not detect typical LSS symptom development and occurrence of surgery during the six-year period. Full article

In recent years, the teleoperation of robots has become widespread in practical use. However, in some current modes of robot operation, such as leader-follower control, the operator must use visual information to recognize the physical deviation between him/herself and the robot, and correct the operation instructions sequentially, which limits movement speed and places a heavy burden on the operator. In this study, we propose a leader-follower control parameter optimization method for the feedforward correction necessitated by deviations in the link length between the robot and the operator. To optimize the parameters, we used the Digital Annealer developed by Fujitsu Ltd., which can solve the combinatorial optimization problem at high speed. The main objective was to minimize the difference between the hand coordinates target and the actual hand position of the robot. In simulations, the proposed method decreased the difference between the hand position of the robot and the target. Moreover, this method enables optimum operation, in part by eliminating the need for the operator to maintain an unreasonable posture, as in some robots the operator’s hand position is unsuitable for achieving the objective. Full article

Background and Objectives: The high prevalence of lumbar spinal stenosis (LSS) and its negative impact on quality of life in the elderly is well known. However, the longitudinal time course of LSS symptoms remains unclear. The purpose of this study was to clarify the longitudinal time course and associated factors of LSS symptoms over a period of six years in a community. Materials and Methods: This study was conducted with data prospectively collected in 2004 and 2010 under a retrospective design. In 2004, 1578 subjects (age range: 40 to 79 years) were interviewed on LSS symptoms using a specially designed and validated questionnaire. In 2010, a follow-up study was performed by mail, to which 789 subjects of the 2004 study population responded. Considering that the presence of osteoarthritis (OA) of the knee or hip may influence the participants’ answers in the questionnaire, analysis was performed in all 789 subjects with and 513 subjects without either knee or hip OA. Changes in LSS symptoms between the initial and the 6-year survey were investigated. Multiple logistic regression analysis was used for detecting the risk factors for LSS symptom presence at the six-year follow-up. Results: 1. At the six-year follow-up, more than half of the subjects who showed LSS symptoms at the initial analysis became LSS-negative, and 12–15% of those who were LSS-negative became LSS-positive. 2. From the multiple logistic regression analysis, a lower Roland-Morris Disability Questionnaire (RDQ) score and a positive LSS symptom at the initial analysis were detected as predictive factors of the presence of LSS symptoms at the six-year follow-up in the total number of subjects, as well as just in those who did not have either knee or hip OA. Conclusions: More than half of the subjects who were LSS-positive at their initial assessment still experienced improvement in their symptoms even after 6 years. This means that both LSS symptoms and their time course vary from person to person. Predictive factors for the presence of LSS symptoms during the six-year follow-up period were RDQ score and positive LSS symptoms. Full article

Many extant studies proposed various stabilizing control methods for humanoids during the stance phase while hopping and running. Although these methods contribute to stability during hopping and running, humanoid robots do not swing their legs rapidly during the flight phase to prevent rotation in the yaw direction. Humans utilize their torsos and arms when running to compensate for the angular momentum in the yaw direction generated by leg movement during the flight phase. In this study, we developed an angular momentum control method based on human motion for a humanoid upper body. The method involves calculation of the angular momentum generated by the movement of the humanoid legs and calculation of the torso and arm motions required to compensate for the angular momentum of the legs in the yaw direction. We also developed a humanoid upper-body mechanism having human link length and mass properties, using carbon-fiber-reinforced plastic and a symmetric structure for generating large angular momentum. The humanoid robot developed in this study could generate almost the same angular momentum as that of a human. Furthermore, when suspended in midair, the humanoid robot achieved angular momentum compensation in the yaw direction. Full article

Analysis of human running has revealed that the motion of the human leg can be modeled by a compression spring because the joints of the leg behave like a torsion spring in the stance phase. In this paper, we describe the development of a joint mechanism that mimics the elastic characteristics of the joints of the stance leg. The knee was equipped with a mechanism comprising two laminated leaf springs made of carbon fiber-reinforced plastic for adjusting the joint stiffness and a worm gear in order to achieve active movement. Using this mechanism, we were able to achieve joint stiffness mimicking that of a human knee joint that can be adjusted by varying the effective length of one of the laminated leaf springs. The equation proposed for calculating the joint stiffness considers the difference between the position of the fixed point of the leaf spring and the position of the rotational center of the joint. We evaluated the performance of the laminated leaf spring and the effectiveness of the proposed equation for joint stiffness. We were able to make a bipedal robot run with one leg using pelvic oscillation for storing energy produced by the resonance related to leg elasticity. Full article