A study on computer vision for facial emotion recognition

Artificial intelligence has been successfully applied in various fields, one of which is computer vision. In this study, a deep neural network (DNN) was adopted for Facial emotion recognition (FER). One of the objectives in this study is to identify the critical facial features on which the DNN model focuses for FER. In particular, we utilized a convolutional neural network (CNN), the combination of squeeze-and-excitation network and the residual neural network, for the task of FER. We utilized AffectNet and the Real-World Affective Faces Database (RAF-DB) as the facial expression databases that provide learning samples for the CNN. The feature maps were extracted from the residual blocks for further analysis. Our analysis shows that the features around the nose and mouth are critical facial landmarks for the neural networks. Cross-database validations were conducted between the databases. The network model trained on AffectNet achieved 77.37% accuracy when validated on the RAF-DB, while the network model pretrained on AffectNet and then transfer learned on the RAF-DB results in validation accuracy of 83.37%. The outcomes of this study would improve the understanding of neural networks and assist with improving computer vision accuracy.

InVestiGation of the Association of Physical Activity and Sedentary Behavior with tHe Occurrence of Future Cardiovascular Disease and Long Term Outcome in General Population Using the HEALTHCARE Database (VGH-HEALTHCARE)

BACKGROUND

Current evidence supports the beneficial effect of physical activity in reducing adverse events, however studies on Asian populations are limited and have reported inconsistent findings. The aim of this study was to investigate the association between physical activity and the development of cardiovascular disease, diabetes, hypertension and malignancy in a large Asian cohort. We also investigated interactions between the intensity of physical activity, environmental exposure and biochemical markers.

METHODS

Subjects who received annual checkups at Taipei Veterans General Hospital were invited to join this study. Information on physical activity was evaluated using the International Physical Activity Questionnaire Short Form (IPAQ-SF). Associations between the occurrence of clinical events including cardiovascular events, diabetes and malignancies and the intensity of physical activity, biochemical markers, imaging findings, personality trait evaluations and nutrition were evaluated.

RESULTS

In the initial stage of this study, a total of 1010 patients enrolled, 626 (62%) were male, 74 (7.4%) had diabetes, 183 (18.3%) had hypertension, and 220 (21.8%) were smokers. The total cholesterol was 202.1 ± 36.2 mg/dL and low-density lipoprotein-cholesterol was 125.7 ± 32.9 mg/dL, including 49.3 ± 13.1 mg/dL for serum high-density lipoprotein-cholesterol and 120.7 ± 70.7 mg/dL for triglycerides. The fasting glucose level was 93.8 ± 21.9 mg/dL, and HbA1c was 5.7 ± 0.7%. All information collected will be incorporated with future events to analyze the relationship between biochemical parameters, physical activity and future adverse events.

CONCLUSIONS

These findings will contribute to the understanding of the value of physical activity in determining future cardiovascular and non-cardiovascular events in Asian populations.

Risk of osteoporosis and fracture in victims with burn injury

Osteoporosis is a well-known bone disorder affecting people worldwide. Patients with osteoporosis have an increased risk of bone fracture. This study provides new information on the risk of developing osteoporosis post burn injury and the risk of fracture among those with osteoporosis developed.

INTRODUCTION

The relationship between burn injury and hip fracture risk is unclear. Population-based evaluation on relationships between burn injury and osteoporosis development and subsequent fractures is limited. We conducted a retrospective cohort study as the investigation.

METHODS

From the insurance data of Taiwan, we established a cohort of 43,532 patients with a burn injury in 2000-2012 and a comparison cohort of 174,124 individuals without such an injury, frequency matched by sex, age, and diagnosis date. Both cohorts were followed up to the end of 2013 to evaluate the occurrence of osteoporosis and hip fracture.

RESULTS

The incidence of osteoporosis was greater in the burn cohort than in the comparison cohort (6.40 vs. 4.75 per 1,000 person-years) with an adjusted IRR of 1.35 (95% confidence interval = 1.32-1.39). The incidence rates in both cohorts were greater in women than in men, increased with age, income, and Charlson comorbidity index. Patients with burns involving 20%-49% of total body surface area and with burns confined to the lower/upper limbs had the greatest incidence rates, 8.32 and 8.58 per 1,000 person-years, respectively. Osteoporosis incidence increased further to 22.7 per 1,000 person-years for burn victims with comorbid diabetes. The risk of fracture was over five-fold greater for burn victims with osteoporosis developed than for comparisons without osteoporosis.

CONCLUSION

Patients who have a burn injury deserve prevention intervention to reduce the risk of osteoporosis and fracture.

High health literacy is associated with less obesity and lower Framingham risk score: Sub-study of the VGH-HEALTHCARE trial

Backgrounds

Lower health literacy (HL) is associated with several cardiovascular disease (CVD) risk factors such as diabetes, hypertension, and metabolic syndrome (MS). The aim of our study was to investigate the association between HL and the Framingham 10-year risk score of CVD.

Methods

From 2015–2016, 1010 subjects aged 23 to 88 years receiving health check-up in Taipei Veterans General Hospital had complete clinical evaluations and laboratory examinations. Fatty liver was diagnosed by ultrasonography. The short form questionnaire adapted from the Mandarin Health Literacy Scale was used to assess HL. The Framingham risk score was calculated by patient characteristics.

Results

Subjects with higher BMIs were associated with lower HL scores. The proportion of subjects with MS was higher in the lower health literacy score group (≤ 9) at 28.8%; further analysis found that lower HL was significantly associated with MS in women but not in men. The Spearman’s rho demonstrated that the HL score was significantly associated with the BMI-based (rho = -0.11; P < 0.001) or lipid-based (rho = -0.09; P < 0.004) Framingham risk score.

Conclusions

Higher HL scores were associated with less CVD risk such as lower BMIs, less MS in women, and less fatty liver disease. Furthermore, HL had an inverse association with the Framingham risk score as expected. Therefore, HL in patients with CVD risk should be improved and considered as an important issue in terms of CVD reduction.

Hip fracture risk in patients with burn injury: a retrospective cohort study in Taiwan

This work aimed to evaluate the hip fracture risk for patients with burn injury. A total of 16,430 patients with burn injury had an adjusted hazard ratio of 1.54 to encounter a hip fracture, compared with controls without the injury. These results encourage future studies focusing on mechanisms leading to fracture associated with burn injury.

INTRODUCTION

The relationship between burn injury and hip fracture risk is unclear. We conducted a retrospective cohort study to investigate this relationship.

METHODS

From insurance data of Taiwan, we identified a cohort with 16,430 burn patients in 2000-2010 and a comparison cohort of 65,716 persons without the history of burn, frequency matched by sex, age, and diagnosis date. Both cohorts were followed up to the end of 2011 to evaluate the risk of hip fracture.

RESULTS

Patients with burn injury were 1.62-fold more likely than comparisons to encounter a hip fracture (6.95 vs. 4.28 per 1000 person-years), with an adjusted hazard ratio (aHR) of 1.54 (95% confidence interval (CI) = 1.40-1.68). The fracture incidence increased with age and is slightly greater for women than for men in both cohorts. The fracture risk was greater for patients with burn in the eyes, face, and head with an incidence of 7.14 per 1000 person-years, or an aHR of 2.09 (95% CI = 1.53, 2.86). Diabetes and osteoporosis were also associated with an increased hip fracture risk.

CONCLUSION

Burn injury is associated with an increased risk of hip fracture. Diabetes and osteoporosis are associated with an enhanced risk.

Nonconservative higher-order hydrodynamic modulation instability

The modulation instability (MI) is a universal mechanism that is responsible for the disintegration of weakly nonlinear narrow-banded wave fields and the emergence of localized extreme events in dispersive media. The instability dynamics is naturally triggered, when unstable energy sidebands located around the main energy peak are excited and then follow an exponential growth law. As a consequence of four wave mixing effect, these primary sidebands generate an infinite number of additional sidebands, forming a triangular sideband cascade. After saturation, it is expected that the system experiences a return to initial conditions followed by a spectral recurrence dynamics. Much complex nonlinear wave field motion is expected, when the secondary or successive sideband pair that is created is also located in the finite instability gain range around the main carrier frequency peak. This latter process is referred to as higher-order MI. We report a numerical and experimental study that confirms observation of higher-order MI dynamics in water waves. Furthermore, we show that the presence of weak dissipation may counterintuitively enhance wave focusing in the second recurrent cycle of wave amplification. The interdisciplinary weakly nonlinear approach in addressing the evolution of unstable nonlinear waves dynamics may find significant resonance in other nonlinear dispersive media in physics, such as optics, solids, superfluids, and plasma.

Enhancing Survival of Human Hepatocytes by Neonatal Thymectomy and Partial Hepatectomy in Micro-miniature Pigs

BACKGROUND

With the goal of in vivo cultivation of human hepatocytes that have not been sufficient in full differentiation in vitro, the advantage of neonatal thymectomy was verified on expansion of xenogeneic human hepatocyte in the micro-miniature pig (MMP).

METHODS

The thymus was excised immediately after the birth of the MMPs via cesarean section. Newborns were fed by artificial feeding under specific pathogen-free conditions. The thymectomized and nonthymectomized littermates were transplanted with human hepatocytes via a portal vein with or without partial hepatectomy at the MMP adult stage.

RESULTS

The growth of thymectomized MMPs and the sham operated littermates was not significantly different; the former weighed 1.98 ± 0.30 kg (average ± standard deviation, n = 4) and the latter weighed 2.28 ± 0.39 kg (n = 4) at 1 month of age, and 17.48 ± 1.92 kg and 16.75 ± 2.68 kg at 12 months of age. Blood thymosin α₁ concentrations in the thymectomy group were significantly lower than in the control group (0.22 ± 0.05 ng/mL vs 0.46 ± 0.16 ng/mL; n = 4, 12 months old, P = .029). After human hepatocyte transplantation, human albumin levels were detectable on day 28 in the peripheral blood of the thymectomy plus hepatectomy group (14.3 ± 4.9 ng/mL [± range, n = 2]) but were not detectable even on day 21 in the control group.

CONCLUSIONS

Neonatal thymectomy was successfully achieved in infantile MMPs born via cesarean section. These pigs were considered to be an ideal in vivo bioreactor for human hepatocytes.

Modulation Instability and Phase-Shifted Fermi-Pasta-Ulam Recurrence

Instabilities are common phenomena frequently observed in nature, sometimes leading to unexpected catastrophes and disasters in seemingly normal conditions. One prominent form of instability in a distributed system is its response to a harmonic modulation. Such instability has special names in various branches of physics and is generally known as modulation instability (MI). The MI leads to a growth-decay cycle of unstable waves and is therefore related to Fermi-Pasta-Ulam (FPU) recurrence since breather solutions of the nonlinear Schrödinger equation (NLSE) are known to accurately describe growth and decay of modulationally unstable waves in conservative systems. Here, we report theoretical, numerical and experimental evidence of the effect of dissipation on FPU cycles in a super wave tank, namely their shift in a determined order. In showing that ideal NLSE breather solutions can describe such dissipative nonlinear dynamics, our results may impact the interpretation of a wide range of new physics scenarios.

Evaluation of nasal patency by visual analogue scale/nasal obstruction symptom evaluation questionnaires and anterior active rhinomanometry after septoplasty: a retrospective one-year follow-up cohort study

OBJECTIVE

To assess the efficacy of septoplasty and the correlation between the subjective evaluations of a visual analogue scale (VAS) and the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire and active anterior rhinomanometry of the nasal airway after septoplasty.

DESIGN

A retrospective, individual cohort study.

SETTING

Ear, Nose and Throat Department, Taipei City Hospital, Taipei, Taiwan.

PARTICIPANTS

Fifty patients with chronic nasal obstruction were enrolled in the study. All 50 patients underwent septoplasty because of nasal septal deviation. Another 28 patients without nasal symptoms served as controls.

MAIN OUTCOME MEASURES

VAS, NOSE and active anterior rhinomanometry were used to measure the sensation of nasal obstruction. All measurements were performed in both groups preoperatively and then repeated on three postoperative visits (3, 6 and 12 months).

RESULTS

The mean VAS score, NOSE score and the nasal resistance in the narrow side of the nose in the study group showed reduced symptoms at 3, 6 and 12 months postoperatively compared with the respective preoperative measurements (P < 0.001, all). The VAS and NOSE scores did not significantly correlate with total nasal resistance preoperatively or postoperatively. The VAS and nasal resistance in the obstructed nasal cavity correlated significantly preoperatively (P < 0.05), but not postoperatively.

CONCLUSIONS

The subjective and objective symptoms of nasal obstruction had improved 1 year after septoplasty. A significant correlation between VAS scores and nasal resistance in the narrow side of the nose was found before surgery. The subjective and objective measurements of nasal obstruction lacked significant correlation postoperatively.

Lower Barthel Index Is Associated with Higher Risk of Hospitalization-Requiring Pneumonia in Long-Term Care Facilities

Pneumonia is an important infectious entity that affects residents in long-term care facilities (LTCFs), whereas hospitalization-requiring pneumonia (HRP) represents a more critical patient condition with worse outcomes. The evidence addressing the association between Barthel index and risk of HRP among LTCF residents is lacking. A multicenter, retrospective cohort study was conducted in three LTCFs enrolling adult patients who resided for 3 months or more and ever underwent Barthel index evaluation within a study period of January 1 to December 31, 2010. The endpoint was HRP after enrollment. A total of 299 patients (169 women; age, 79.0 ± 12.2 years) were enrolled and categorized into HRP Group (n = 68; 36 women; age, 79.1 ± 11.3 years) and Non-HRP Group (n = 231; 133 women; age, 79.0 ± 12.4 years) by the endpoint. The patients in HRP Group had significantly lower Barthel index (8.6 versus 25.8 points, p < 0.001) but higher proportion of chronic obstructive pulmonary disease (13.2% versus 3.9%, p = 0.004). By the multivariate analysis of logistic regression, we found that lower Barthel index (odds ratio (OR), 0.967; p < 0.001), existence of chronic obstructive pulmonary disease (OR, 4.192; p = 0.015), and feeding route (percutaneous endoscopic gastrostomy comparing with oral feeding; OR, 0.177; p = 0.012) were independently associated with HRP. In conclusion, a lower Barthel index is significantly associated with the occurrence of pneumonia that requires hospitalization in long-term care residents. Barthel index is a useful and reliable tool for risk evaluation in this population.

Alveolar bone-loss area localization in periodontitis radiographs based on threshold segmentation with a hybrid feature fused of intensity and the H-value of fractional Brownian motion model

BACKGROUND AND OBJECTIVE

Periodontitis involves progressive loss of alveolar bone around the teeth. Hence, automatic alveolar bone-loss (ABL) measurement in periapical radiographs can assist dentists in diagnosing such disease. In this paper, we propose an effective method for ABL area localization and denote it as ABLIfBm.

METHOD

ABLIfBm is a threshold segmentation method that uses a hybrid feature fused of both intensity and texture measured by the H-value of fractional Brownian motion (fBm) model, where the H-value is the Hurst coefficient in the expectation function of a fBm curve (intensity change) and is directly related to the value of fractal dimension. Adopting leave-one-out cross validation training and testing mechanism, ABLIfBm trains weights for both features using Bayesian classifier and transforms the radiograph image into a feature image obtained from a weighted average of both features. Finally, by Otsu's thresholding, it segments the feature image into normal and bone-loss regions.

RESULTS

Experimental results on 31 periodontitis radiograph images in terms of mean true positive fraction and false positive fraction are about 92.5% and 14.0%, respectively, where the ground truth is provided by a dentist. The results also demonstrate that ABLIfBm outperforms (a) the threshold segmentation method using either feature alone or a weighted average of the same two features but with weights trained differently; (b) a level set segmentation method presented earlier in literature; and (c) segmentation methods based on Bayesian, K-NN, or SVM classifier using the same two features.

CONCLUSION

Our results suggest that the proposed method can effectively localize alveolar bone-loss areas in periodontitis radiograph images and hence would be useful for dentists in evaluating degree of bone-loss for periodontitis patients.

Excitons and biexcitons in InGaN quantum dot like localization centers

Indium segregation in a narrow InGaN single quantum well creates quantum dot (QD) like exciton localization centers. Cross-section transmission electron microscopy reveals varying shapes and lateral sizes in the range ∼1-5 nm of the QD-like features, while scanning near field optical microscopy demonstrates a highly inhomogeneous spatial distribution of optically active individual localization centers. Microphotoluminescence spectroscopy confirms the spectrally inhomogeneous distribution of localization centers, in which the exciton and the biexciton related emissions from single centers of varying geometry could be identified by means of excitation power dependencies. Interestingly, the biexciton binding energy (E(b)xx) was found to vary from center to center, between 3 to -22 meV, in correlation with the exciton emission energy. Negative binding energies are only justified by a three-dimensional quantum confinement, which confirms QD-like properties of the localization centers. The observed energy correlation is proposed to be understood as variations of the lateral extension of the confinement potential, which would yield smaller values of E(b)xx for reduced lateral extension and higher exciton emission energy. The proposed relation between lateral extension and E(b)xx is further supported by the exciton and the biexciton recombination lifetimes of a single QD, which suggest a lateral extension of merely ∼3 nm for a QD with strongly negative E(b)xx = -15.5 meV.

Teeth segmentation of dental periapical radiographs based on local singularity analysis

Teeth segmentation for periapical raidographs is one of the most critical tasks for effective periapical lesion or periodontitis detection, as both types of anomalies usually occur around tooth boundaries and dental radiographs are often subject to noise, low contrast, and uneven illumination. In this paper, we propose an effective scheme to segment each tooth in periapical radiographs. The method consists of four stages: image enhancement using adaptive power law transformation, local singularity analysis using Hölder exponent, tooth recognition using Otsu's thresholding and connected component analysis, and tooth delineation using snake boundary tracking and morphological operations. Experimental results of 28 periapical radiographs containing 106 teeth in total and 75 useful for dental examination demonstrate that 105 teeth are successfully isolated and segmented, and the overall mean segmentation accuracy of all 75 useful teeth in terms of (TP, FP) is (0.8959, 0.0093) with standard deviation (0.0737, 0.0096), respectively.

In-plane magnetization-induced quantum anomalous Hall effect

The quantum Hall effect can only be induced by an out-of-plane magnetic field for two-dimensional electron gases, and similarly, the quantum anomalous Hall effect has also usually been considered for systems with only out-of-plane magnetization. In the present work, we predict that the quantum anomalous Hall effect can be induced by in-plane magnetization that is not accompanied by any out-of-plane magnetic field. Two realistic two-dimensional systems, Bi2Te3 thin film with magnetic doping and HgMnTe quantum wells with shear strains, are presented and the general condition for the in-plane magnetization-induced quantum anomalous Hall effect is discussed based on the symmetry analysis. Nonetheless, an experimental setup is proposed to confirm this effect, the observation of which will pave the way to search for the quantum anomalous Hall effect in a wider range of materials.

Improvement of hepatocyte recovery from rat liver subjected to 1-hour warm ischemic injury by using citrate phosphate dextrose added to euro-collins perfusion solution

Warm ischemia (WI)-related injury interferes with recovery of primary hepatocyte after collagenase digestion of surgically resected or non-heart-beating donor livers as human cell sources. We speculated that digestion is impaired due to reduced microcirculation, caused by microembolism after WI. We sought to improve hepatocyte recovery after WI using a rat model. Anesthetized 9-week-old male Sprague-Dawley rats underwent a midline abdominal incision to insert a 22-gauge cannula into the portal vein. WI was initiated by ligating both the cannula and the hepatic artery. We compared Euro-Collins (EC) perfusion solution with 2 anticoagulants-heparin or citrate phosphate dextrose (CPD)-versus ethylene glycol tetraacetic acid (EGTA) combined with Ca(2+)- and Mg(2+)-free Hank's solution (CM-free Hank's solution). Use of CM-free Hank's solution yielded only 0.75 ± 0.15 × 10(8) and 0.82 ± 0.20 × 10(8) cells at 30 and 60 minutes WI respectively. However, CPD, but not heparin, added to the EC solution produced the best cell recovery (CPD: 2.15 ± 0.38 × 10(8); heparin: 1.63 ± 0.31 × 10(8)). During macroscopic observation, CPD added to EC solution also demonstrated best blood flushing. CPD added to EC solution achieved greater hepatocyte recovery than CM-free Hank's solution by restoring microcirculation during flushing of blood from liver tissue subjected to WI.

Citrus reticulata peel improves patient tolerance of low-volume polyethylene glycol for colonoscopy preparation

BACKGROUND

Adequate adjuncts help to reduce the volume of polyethylene glycol-electrolyte lavage solution (PEG-ELS) needed, to ameliorate patient discomfort, and to improve colonic visibility during colonoscopy. This study aimed to assess the effect of Citrus reticulata peel (CRP) as an adjunct to low-volume PEG for colonic preparation.

METHODS

A total of 1092 health examination examinees received colonoscopy during the study period. After excluding those who refused to participate and those who did not meet our criteria, 212 examinees were enrolled into this study. They were divided into the PEG group and the PEG + CRP group according to their date of examination. All examinees received 2 L of PEG-ELS one day before colonoscopy. The PEG + CRP group also received additional CRP in the form of a "buccal tablet" between drinks. Tolerance and adverse events were assessed by questionnaire, while the quality of bowel preparation for colonoscopy was scored by an endoscopist.

RESULTS

There were 107 examinees in the PEG group and 105 examinees in the PEG + CRP group. The demographic characteristics of the examinees were comparable between these two groups. Examinees in the PEG + CRP group had a trend of better colonic visibility than those in the PEG group (p = 0.056). Moreover, examinees in the PEG + CRP group had higher rate of acceptable taste (p = 0.015) and lower rate of difficulty swallowing (p = 0.001). The incidences of adverse events including vomiting (p = 0.045), bloating (p = 0.035), and difficulty sleeping (p < 0.001) were also significantly lower in the PEG + CRP group.

CONCLUSION

Compared with conventional colonic preparation, the application of CRP as an adjunct could improve examinees' tolerance, decrease the incidence of adverse events, and maintain the quality of colonic cleansing.

Magnetic ground state and transition of a quantum multiferroic LiCu2O2

Based on resonant soft x-ray magnetic scattering, we report that LiCu2O2 exhibits a large interchain coupling which suppresses quantum fluctuations along spin chains, and a quasi-2D short-range magnetic order prevails at temperatures above the magnetic transition. These observations unravel the fact that the ground state of LiCu2O2 possesses long-range 2D-like incommensurate magnetic order rather than being a gapped spin liquid as expected from the nature of quantum spin-1/2 chains. In addition, the spin coupling along the c axis is found to be essential for inducing electric polarization.

Aligned Er-doped ZnO nanorod arrays with enhanced 1.54 microm infrared emission

Vertically aligned Er-doped ZnO nanorod arrays with sharp and intense 1.54 microm infrared emission have been fabricated on Si substrates through a well controlled spin-coating and annealing process. The synthesis method is advantageous for synthesizing ZnO nanostructures free from structural defects, capability for large-scale production, minimum equipment requirement and product homogeneity. Er atoms were found to incorporate into ZnO lattice from XRD, ESCA, TEM, STEM/EDS and PL measurements. The single-crystal Er-doped nanorods maintained their high microstructural quality after annealing for 4 hr at 800 degreesC. The intensity of 1.54 microm infrared emission was found to be correlated with the deep level green emission. The enhanced luminescence intensity and best ever narrow wavelength distribution of Er-doped ZnO nanorod arrays at 1.54 microm emission will be conductive to applications in optoelectronic devices and optical communications.

Efficacy of a modified improved technique for detecting red cell haemoglobin H inclusions

Alpha-thalassaemia is a common disease in Taiwan. A feature useful in diagnosis is the excess of of beta-chains that result from impaired alpha-chain production. These excess chains assemble into beta 4 tetramers (i.e. Hb H) which can be detected by its rapid anodal migration on alkaline electrophoretic media as seen in Hb H disease. However, this technique cannot, and conventional Hb H inclusion staining rarely can visualize alpha-thalassaemic traits due to small quantities of Hb H formed in these patients. The staining for Hb H inclusion bodies uses brilliant cresyl blue (BCB) or methylene blue (MB) as an oxidant to denature Hb H as intracellular inclusions. We have improved the technique of Jones (who modified the original method in order to obtain enriched young red cells) by prolonging the incubation time from 30 min to 3 h. The sensitivity of this modified improved method was 91% for detecting obligatory alpha-thalassaemic traits as shown in table. No false positive results were seen in beta-thalassaemia or in others. We believe this can be used as a confirmatory test in heterozygous alpha 1-thalassaemia and homozygous alpha 2-thalassaemia.