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1.
IEEE Trans Image Process ; 32: 6289-6302, 2023.
Article in English | MEDLINE | ID: mdl-37963008

ABSTRACT

Head pose estimation (HPE) is an indispensable upstream task in the fields of human-machine interaction, self-driving, and attention detection. However, practical head pose applications suffer from several challenges, such as severe occlusion, low illumination, and extreme orientations. To address these challenges, we identify three cues from head images, namely, critical minority relationships, neighborhood orientation relationships, and significant facial changes. On the basis of the three cues, two key insights on head poses are revealed: 1) intra-orientation relationship and 2) cross-orientation relationship. To leverage two key insights above, a novel relationship-driven method is proposed based on the Transformer architecture, in which facial and orientation relationships can be learned. Specifically, we design several orientation tokens to explicitly encode basic orientation regions. Besides, a novel token guide multi-loss function is accordingly designed to guide the orientation tokens as they learn the desired regional similarities and relationships. Experimental results on three challenging benchmark HPE datasets show that our proposed TokenHPE achieves state-of-the-art performance. Moreover, qualitative visualizations are provided to verify the effectiveness of the token-learning methodology.


Subject(s)
Cues , Learning , Humans , Benchmarking , Face/diagnostic imaging , Lighting
2.
JAMA Psychiatry ; 80(7): 665-674, 2023 07 01.
Article in English | MEDLINE | ID: mdl-37195676

ABSTRACT

Importance: Suicide is a leading cause of deaths in the US. Although the emergency department (ED) is an opportune setting, ED-initiated interventions remain underdeveloped and understudied. Objective: To determine if an ED process improvement package, with a subfocus on improving the implementation of collaborative safety planning, reduces subsequent suicide-related behaviors. Design, Setting, and Participants: The Emergency Department Safety Assessment and Follow-up Evaluation 2 (ED-SAFE 2) trial, a stepped-wedge cluster randomized clinical trial conducted in 8 EDs across the US, used an interrupted time series design with three 12-month sequential phases: baseline, implementation, and maintenance. A random sample of 25 patients per month per site 18 years and older who screened positive on the Patient Safety Screener, a validated suicide risk screener, were included. The primary analyses focused on those who were discharged from the ED, while secondary analyses focused on all patients who screened positive, regardless of disposition. Data were collected on patients who presented for care from January 2014 to April 2018, and data were analyzed from April to December 2022. Interventions: Each site received lean training and built a continuous quality improvement (CQI) team to evaluate the current suicide-related workflow in the ED, identify areas of improvement, and implement efforts to improve. Each site was expected to increase their universal suicide risk screening and implement collaborative safety planning for patients at risk of suicide who were discharged home from the ED. Site teams were centrally coached by engineers experienced in lean CQI and suicide prevention specialists. Main Outcomes and Measures: The primary outcome was a composite comprising death by suicide or suicide-related acute health care visits, measured over a 6-month follow-up window. Results: Across 3 phases, 2761 patient encounters were included in the analyses. Of these, 1391 (50.4%) were male, and the mean (SD) age was 37.4 (14.5) years. A total of 546 patients (19.8%) exhibited the suicide composite during the 6-month follow-up (9 [0.3%] died by suicide and 538 [19.5%] of a suicide-related acute health care visit). A significant difference was observed for the suicide composite outcome between the 3 phases (baseline, 216 of 1030 [21%]; implementation, 213 of 967 [22%]; maintenance, 117 of 764 [15.3%]; P = .001). The adjusted odds ratios of risk of the suicide composite during the maintenance phase was 0.57 (95% CI, 0.43-0.74) compared with baseline and 0.61 (0.46-0.79) compared with the implementation phase, which reflect a 43% and 39% reduction, respectively. Conclusions and Relevance: In this multisite randomized clinical trial, using CQI methods to implement a department-wide change in suicide-related practices, including the implementation of a safety plan intervention, yielded a significant decrease in suicide behaviors in the maintenance period of the study. Trial Registration: ClinicalTrials.gov Identifier: NCT02453243.


Subject(s)
Suicide , Humans , Male , Adult , Female , Suicidal Ideation , Suicide Prevention , Emergency Service, Hospital
3.
Geriatr Gerontol Int ; 20(4): 343-347, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32064723

ABSTRACT

AIM: Cognitive impairment and functional deterioration are common in later life and often co-occur with depressive symptoms (DS). This study aims to examine the individual effects and possible interaction between worsening cognitive function (CF) and deteriorating functional status (FS) on DS using large sample, longitudinal data. METHODS: Elderly people who completed the baseline survey of China Health and Retirement Longitudinal Study (CHARLS 2011) and the third wave survey (2015) were included. A multivariable logistic regression model was used to assess the individual effects. The relative excess risk due to interaction (RERI), the attributable proportion due to interaction (AP) and synergy index (SI) were calculated to evaluate the additive interaction. RESULTS: Worsening CF and deteriorating FS were associated with the increase in DS, while unchanged or improved CF and FS were associated with the decrease in DS. In addition, decreased (increased) FS led to more severe (improved) DS than decreased (increased) CF. The additive interaction between worsening CF and deteriorating FS on the increase in DS was significant. The estimates and 95% CI of the RERI, AP and SI were 0.626 (0.061, 1.190), 0.222 (0.042, 0.402) and 1.526 (1.016, 2.291) respectively. CONCLUSIONS: Both worsening CF and deteriorating FS have positive interactions with the increase in DS. It is vital to focus on DS of elderly people with worsening CF and/or FS and to adopt interventions. Geriatr Gerontol Int 2020; 20: 343-347.


Subject(s)
Cognition/physiology , Cognitive Dysfunction/epidemiology , Depression/epidemiology , Physical Functional Performance , Activities of Daily Living , Aged , China/epidemiology , Cognitive Dysfunction/complications , Depression/complications , Female , Humans , Independent Living , Logistic Models , Longitudinal Studies , Male , Risk Factors , Surveys and Questionnaires
4.
Int J Geriatr Psychiatry ; 34(12): 1892-1899, 2019 12.
Article in English | MEDLINE | ID: mdl-31469190

ABSTRACT

OBJECTIVES: Little research has explored how cognitive function and activities of daily living (ADL) affect each other over time. In addition, no current finding provides a clear hint to the temporal precedence between them. The present study tries to address these limitations of prior studies by utilizing a longitudinal data and advanced statistical modeling. METHODS: This study analyzed the data from the China Health and Retirement Longitudinal Study (CHARLS), a prospective observational study performed every 2 years for a total of three waves between 2011 and 2015 using a multistage probability sampling. Cognitive function was measured on the basis of three aspects of cognitive performance. Functional abilities were assessed using six types of activities of ADL and five types of instrumental ADL (IADL). Latent difference score modeling was employed to investigate the temporal precedence between cognitive function and ADL. RESULTS: The best fitting model indicates poor cognitive function precede worsening in ADL function, whereas the current findings did not support that poor ADL predate the cognition decline or reciprocal influence hypotheses. CONCLUSIONS: The elderly with poor cognitive function may be more vulnerable to deterioration in ADL. Findings underscore the importance of early screening for cognitive function among the elderly as the key strategy to prevent further ADL impairment and keep independence.


Subject(s)
Activities of Daily Living/psychology , Cognition/physiology , Cognitive Dysfunction/complications , Aged , Aged, 80 and over , China , Female , Humans , Independent Living , Longitudinal Studies , Male , Prospective Studies
5.
Neural Regen Res ; 14(9): 1603-1609, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31089060

ABSTRACT

Curcumin exerts a neuroprotective effect on Alzheimer's disease; however, it is not known whether microRNAs are involved in this protective effect. This study was conducted using swAPP695-HEK293 cells as an Alzheimer's disease cell model. swAPP695-HEK293 cells were treated with 0, 0.5, 1, 2, 5, and 10 µM curcumin for 24 hours. The changes in miR-15b-5p, miR-19a-3p, miR-195-5p, miR-101-3p, miR-216b-5p, miR-16-5p and miR-185-5p expression were assessed by real-time quantitative polymerase chain reaction. The mRNA and protein levels of amyloid precursor protein, amyloid-ß40 and amyloid-ß42 were evaluated by quantitative real-time polymerase chain reaction, western blot assays and enzyme-linked immunosorbent assays. swAPP695-HEK293 cells were transfected with miR-15b-5p mimic, or treated with 1 µM curcumin 24 hours before miR-15b-5p inhibitor transfection. The effects of curcumin on amyloid precursor protein, amyloid-ß40 and amyloid-ß42 levels were evaluated by western blot assays and enzyme-linked immunosorbent assay. Luciferase assays were used to analyze the interaction between miR-15b-5p and the 3'-untranslated region of amyloid precursor protein. The results show that amyloid precursor protein and amyloid-ß expression were enhanced in swAPP695-HEK293 cells compared with HEK293 parental cells. Curcumin suppressed the expression of amyloid precursor protein and amyloid-ß and up-regulated the expression of miR-15b-5p in swAPP695-HEK293 cells. In addition, we found a negative association of miR-15b-5p expression with amyloid precursor protein and amyloid-ß levels in the curcumin-treated cells. Luciferase assays revealed that miR-15b-5p impaired the luciferase activity of the plasmid harboring the 3'-untranslated region of amyloid precursor protein. These findings indicate that curcumin down-regulates the expression of amyloid precursor protein and amyloid-ß in swAPP695-HEK293 cells, which was partially mediated by miR-15b-5p via targeting of the 3'-untranslated region of amyloid precursor protein.

6.
Robotics Biomim ; 4(1): 21, 2017.
Article in English | MEDLINE | ID: mdl-29201604

ABSTRACT

Shadow and background are two common factors in digital fringe projection, which lead to ambiguity in three-dimensional measurement and thereby need to be seriously considered. Preprocessing is often needed to segment the object from invalid points. The existing segmentation approaches based on modulation normally perform well in pure dark background circumstances, which, however, lose accuracy in situations of white or complex background. In this paper, an accurate shadow and background removal technique is proposed, which segments the shadow by one threshold from modulation histogram and segments the background by the threshold in intensity histogram. Experiments are well designed and conducted to verify the effectiveness and reliability of the proposed method.

7.
IEEE Trans Cybern ; 45(4): 663-75, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25029548

ABSTRACT

In this paper, we present a novel appearance model using sparse representation and online dictionary learning techniques for visual tracking. In our approach, the visual appearance is represented by sparse representation, and the online dictionary learning strategy is used to adapt the appearance variations during tracking. We unify the sparse representation and online dictionary learning by defining a sparsity consistency constraint that facilitates the generative and discriminative capabilities of the appearance model. An elastic-net constraint is enforced during the dictionary learning stage to capture the characteristics of the local appearances that are insensitive to partial occlusions. Hence, the target appearance is effectively recovered from the corruptions using the sparse coefficients with respect to the learned sparse bases containing local appearances. In the proposed method, the dictionary is undercomplete and can thus be efficiently implemented for tracking. Moreover, we employ a median absolute deviation based robust similarity metric to eliminate the outliers and evaluate the likelihood between the observations and the model. Finally, we integrate the proposed appearance model with the particle filter framework to form a robust visual tracking algorithm. Experiments on benchmark video sequences show that the proposed appearance model outperforms the other state-of-the-art approaches in tracking performance.

8.
Liver Transpl ; 17(10): 1191-9, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21604357

ABSTRACT

The use of high-risk donor livers, which is reflective of the gross national shortage of organs available for transplantation, has gained momentum. Despite the demand, many marginal livers are discarded annually. We evaluated the impact of center volume on survival outcomes associated with liver transplantation using high-donor risk index (DRI) allografts. We queried the Scientific Registry of Transplant Recipients database for deceased donor liver transplants (n = 31,576) performed between 2002 and 2008 for patients who were 18 years old or older, and we excluded partial and multiple liver transplants. A high-DRI cohort (n = 15,668), which was composed of patients receiving grafts with DRIs > 1.90, was analyzed separately. Transplant centers (n = 102) were categorized into tertiles by their annual procedure volumes: high-volume centers (HVCs; 78-215 cases per year), medium-volume centers (MVCs; 49-77 cases per year), and low-volume centers (LVCs; 5-48 cases per year). The endpoints were allograft survival and recipient survival. In comparison with their lower volume counterparts, HVCs used donors with higher mean DRIs (2.07 for HVCs, 2.01 for MVCs, and 1.91 for LVCs), more donors who were 60 years old or older (18.02% for HVCs, 16.85% for MVCs, and 12.39% for LVCs), more donors who died after a stroke (46.52% for HVCs, 43.71% for MVCs, and 43.36% for LVCs), and more donation after cardiac death organs (5.04% for HVCs, 4.45% for MVCs, and 3.51% for LVCs, all P values < 0.001). Multivariate risk-adjusted frailty models showed that increased procedure volume at a transplant center led to decreased risks of allograft failure [hazard ratio (HR) = 0.93, 95% confidence interval (CI) = 0.89-0.98, P = 0.002] and recipient death (HR = 0.90, 95% CI = 0.83-0.97, P = 0.004) for high-DRI liver transplants. In conclusion, HVCs more frequently used higher DRI livers and achieved better risk-adjusted allograft and recipient survival. A greater understanding of the outcomes of transplantation with high-DRI livers may improve their utilization, the postoperative outcomes, and future allocation practices.


Subject(s)
Donor Selection/statistics & numerical data , Graft Survival , Hospitals/statistics & numerical data , Liver Transplantation/adverse effects , Outcome and Process Assessment, Health Care/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Tissue Donors/supply & distribution , Adult , Chi-Square Distribution , Female , Humans , Kaplan-Meier Estimate , Liver Transplantation/mortality , Male , Middle Aged , Odds Ratio , Proportional Hazards Models , Registries , Regression Analysis , Retrospective Studies , Risk Assessment , Risk Factors , Survival Rate , Time Factors , Treatment Outcome , United States/epidemiology
9.
HPB (Oxford) ; 11(5): 391-7, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19768143

ABSTRACT

BACKGROUND: The optimal management of acute pancreatitis remains controversial and current treatment protocols vary in degrees of medical and surgical management. Our group has previously shown in population-based studies that high-volume (HV) hospitals have lower rates of in-hospital mortality after pancreatectomy. We sought to examine if a similar mortality benefit exists for patients admitted with acute pancreatitis. METHODS: Using the Nationwide Inpatient Sample (NIS), we examined discharge records for all adult admissions during 1998-2006 with a primary diagnosis of acute pancreatitis of any aetiology. Unique hospital identifiers were used to divide hospital volumes into equal thirds based on the number of admissions for acute pancreatitis per year (lowest tertile [low volume, LV] < or = 64 admissions/year; medium tertile [medium volume, MV] 65-117 admissions/year; highest tertile [high volume, HV] > or = 118 admissions/year). Covariates included patient demographics, hospital characteristics and patient co-morbidities using the Elixhauser index. Adjusted mortality represented the primary outcome measure and adjusted length of stay (LOS) and total charges were considered secondary measures. RESULTS: There were 416,489 primary admissions for acute pancreatitis during the study period. In-hospital mortality for the cohort amounted to 1.6% (n = 6446). Hospital admissions for acute pancreatitis increased over the study period (P < 0.0001). High-volume hospitals tended to be large (82%), urban (99%) teaching (59%) centres (P < 0.0001), which cared for patients with more co-morbidities (35.9% of patients at HV hospitals vs. 29.1% at LV hospitals had at least three co-morbidities; P < 0.0001). Low-volume centres appeared more likely to perform pancreatic procedures than HV hospitals (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.32-1.70). Patients at HV hospitals had a lower likelihood of a prolonged adjusted LOS compared with those at LV (OR 0.75, 95% CI 0.71-0.79) or MV (OR 0.82, 95% CI 0.79-0.85) hospitals. After adjusting for patient and hospital factors, there was an in-hospital mortality benefit associated with being treated at an HV centre (OR 0.70, 95% CI 0.63-0.77). The decision to operate on a given patient did not alter the mortality benefit of the HV hospital. CONCLUSIONS: Rates of admissions for acute pancreatitis in the USA are increasing. High annual hospital volume of acute pancreatitis cases confers a shorter LOS, lower adjusted mortality and a lower likelihood of pancreatic procedure for patients admitted with acute pancreatitis. Although HV hospitals were less likely than MV or LV centres to perform pancreatic procedures, the role of surgery remains unclear. Further studies should examine other possible reasons for this mortality benefit, such as the availability of specialists, the quality of critical care facilities and the timing of operative intervention.

10.
IEEE Trans Syst Man Cybern B Cybern ; 38(2): 320-30, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18348917

ABSTRACT

In this paper, a new active visual system is developed, which is based on bionic vision and is insensitive to the property of the cameras. The system consists of a mechanical platform and two cameras. The mechanical platform has two degrees of freedom of motion in pitch and yaw, which is equivalent to the neck of a humanoid robot. The cameras are mounted on the platform. The directions of the optical axes of the two cameras can be simultaneously adjusted in opposite directions. With these motions, the object's images can be located at the centers of the image planes of the two cameras. The object's position is determined with the geometry information of the visual system. A more general model for active visual positioning using two cameras without a neck is also investigated. The position of an object can be computed via the active motions. The presented model is less sensitive to the intrinsic parameters of cameras, which promises more flexibility in many applications such as visual tracking with changeable focusing. Experimental results verify the effectiveness of the proposed methods.


Subject(s)
Algorithms , Artificial Intelligence , Biomimetics/methods , Cybernetics/methods , Image Interpretation, Computer-Assisted/methods , Pattern Recognition, Automated/methods , Robotics/methods , Humans , Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
11.
IEEE Trans Syst Man Cybern B Cybern ; 36(5): 1104-17, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17036816

ABSTRACT

In this paper, a new method is proposed to detect the pose of an object with two cameras. First, the intrinsic parameters of the cameras are self-calibrated with two pairs of parallel lines that are orthogonal. Then, the poses of the cameras relative to the parallel lines are deduced, and the rotational transformation between the two cameras is calculated. With the intrinsic parameters and the relative pose of the two cameras, a method is proposed to obtain the poses of a line, plane, and rigid object. Furthermore, a new visual-control method is developed using a pose detection rather than a three-dimensional reconstruction. Experiments are conducted to verify the effectiveness of the proposed method.


Subject(s)
Algorithms , Artificial Intelligence , Pattern Recognition, Automated/methods , Photogrammetry/instrumentation , Photography/instrumentation , Video Recording/instrumentation , Calibration , Equipment Failure Analysis/methods , Equipment Failure Analysis/standards , Motion , Pattern Recognition, Automated/standards , Photogrammetry/methods , Photography/methods , Photography/standards , Video Recording/methods , Video Recording/standards
13.
J Thromb Thrombolysis ; 15(1): 19-23, 2003 Feb.
Article in English | MEDLINE | ID: mdl-14574072

ABSTRACT

BACKGROUND: Fibrinolytic therapy represents a widely available and effective treatment modality for ST segment elevation myocardial infarction (MI). Its overall benefit is attenuated by a high incidence of coronary arterial reocclusion. METHODS/RESULTS: Human umbilical vein endothelial cells (HUVEC) were incubated with unfractionated heparin (1.5 U/ml) (to provoke tissue factor pathway inhibitor [TFPI] release) followed by the addition of varying concentrations of alteplase (recombinant tissue plasminogen activator), plasminogen, their combination or plasmin alone. In the presence of 20% TFPI-depleted human plasma, there was a concentration-dependent decrease in TFPI levels following incubation with alteplase (28% reduction at 200 ng/ml; P < 0.01); 37% reduction at 1000 ng/ml (P < 0.001). Similar effects were observed for alteplase combined with plasminogen (P < 0.001), plasmin alone (P < 0.001) and with HUVEC incubated with low concentrations of plasmin (10 ng/ml) prior to heparin exposure. CONCLUSIONS: Plasmin, a non-specific protease, degrades vascular endothelial cell (constitutive) TFPI and heparin-releasable TFPI, attenuating an important pathway of vascular surface thromboresistance and potentially contributing to coronary arterial reocclusion after fibrinolytic therapy.


Subject(s)
Endothelium, Vascular/metabolism , Fibrinolysin/physiology , Heparin/pharmacology , Lipoproteins/drug effects , Peptide Hydrolases/metabolism , Coronary Artery Disease/chemically induced , Dose-Response Relationship, Drug , Endothelium, Vascular/cytology , Endothelium, Vascular/physiology , Fibrinolytic Agents/pharmacology , Humans , Lipoproteins/metabolism , Recurrence , Tissue Plasminogen Activator/pharmacology , Umbilical Veins
14.
Am Heart J ; 143(4): 725-32, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11923812

ABSTRACT

BACKGROUND: Platelet surface glycoprotein IIb/IIIa (alphaIIb/beta3) receptor inhibition, with prevention of fibrinogen binding and platelet aggregation, concomitantly attenuates arterial thrombotic capacity and impairs protective hemostasis, 2 divergent platelet-dependent processes. PURPOSE: Because the currently available, Food and Drug Administration-approved small molecule glycoprotein IIb/IIIa receptor antagonists are considered "competitive" inhibitors and there is limited information on the reversibility of platelet inhibition with fibrinogen or platelet supplementation, the following series of in vitro experiments were performed. METHODS AND RESULTS: Washed platelets from 24 healthy volunteers were suspended in tyrodes buffer and incubated with achievable (in vivo) concentrations of either tirofiban or eptifibatide before activation with thrombin receptor agonist peptide (15 micromol/L). Platelet aggregation was inhibited by 40% to 50%, but reversal was achieved with fibrinogen supplementation in a concentration-dependent manner. In a separate series of in vitro experiments, platelet inhibition exceeding 90% was established with tirofiban (average concentration 9.28 microg/L) and eptifibatide (average concentration 95.4 microg/L). Recovery of platelet aggregation to at least 50% was achieved after the addition of fibrinogen (0.76-0.80 g/L), platelets (2.4 x 10(11)/L), or their combination. There was an inverse relationship between plasma baseline fibrinogen and the amount of supplemental fibrinogen needed to restore platelet aggregability (r = -0.60; P <.01). CONCLUSION: The reversibility of glycoprotein IIb/IIIa-directed platelet inhibition is influenced by cell surface receptor availability and intrinsic pharmacodynamic mechanism of action. Fibrinogen supplementation with fresh frozen plasma or cryoprecipitate either alone or in combination with platelet transfusion represents an important and readily available treatment consideration for restoring hemostatic potential and managing major hemorrhagic complications associated with the administration of small-molecule, competitive glycoprotein IIb/IIIa receptor antagonists.


Subject(s)
Blood Platelets/drug effects , Fibrinogen/analysis , Fibrinolytic Agents/pharmacology , Peptides/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Platelet Glycoprotein GPIIb-IIIa Complex/antagonists & inhibitors , Tyrosine/analogs & derivatives , Tyrosine/pharmacology , Adult , Eptifibatide , Humans , Linear Models , Middle Aged , Tirofiban
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