Miracle-dz/UniFAR-FTUs huggingface dataset:
Conceptual design of a novel variable stiffness actuator for use in lower limb exoskeletons

A novel modular variable stiffness actuator (VSA), for use in the knee joint of lower limb exoskeletons, is presented. The actuator consists of a combination of a spindle-driven MACCEPA (Mechanically Adjustable Compliance and Controllable Equilibrium Position Actuator) and a spring acting in parallel, (dis)engaged by means of a simple on/off mechanism depending on the phase of the gait cycle. Such design approach is inspired by two clearly distinctive gait phases of a knee joint, one with a high velocity and low torque, and another one with low velocity and high torque profiles. By tackling each of these two phases separately, energy consumption and torque requirements of an active part of the actuator have been decreased, while keeping the size and the weight of the actuator at a reasonable size for use in wearable robots (WR).
Enhanced penetration into 3D cell culture using two and three layered gold nanoparticles

Nano-scale particles sized 10–400 nm administered systemically preferentially extravasate from tumor vasculature due to the enhanced permeability and retention effect. Therapeutic success remains elusive, however, because of inhomogeneous particle distribution within tumor tissue. Insufficient tumor vascularization limits particle transport and also results in avascular hypoxic regions with non-proliferating cells, which can regenerate tissue after nanoparticle-delivered cytotoxicity or thermal ablation. Nanoparticle surface modifications provide for increasing tumor targeting and uptake while decreasing immunogenicity and toxicity. Herein, we created novel two layer gold-nanoshell particles coated with alkanethiol and phosphatidylcholine, and three layer nanoshells additionally coated with high-density-lipoprotein. We hypothesize that these particles have enhanced penetration into 3-dimensional cell cultures modeling avascular tissue when compared to standard poly(ethylene glycol) (PEG)-coated nanoshells. Particle uptake and distribution in liver, lung, and pancreatic tumor cell cultures were evaluated using silver-enhancement staining and hyperspectral imaging with dark field microscopy. Two layer nanoshells exhibited significantly higher uptake compared to PEGylated nanoshells. This multilayer formulation may help overcome transport barriers presented by tumor vasculature, and could be further investigated in vivo as a platform for targeted cancer therapies.
A Structured Approach for Rapidly Mapping Multilevel System Measures via Simulation Metamodeling

With increasing complexity of real‐world systems, especially for continuously evolving scenarios, systems analysts encounter a major challenge with the modeling techniques that capture detailed system characteristics defining input–output relationships. The models become very complex and require long time of execution. In this situation, techniques to construct approximations of the simulation model by metamodeling alleviate long run times and the need for large computational resources; it also provides a means to aggregate a simulation's multiple outputs of interest and derives a single decision‐making metric. The method described here leverages simulation metamodeling to map the three basic SE metrics, namely, measures of performance to measures of effectiveness to a single figure of merit. This enables using metamodels to map multilevel system measures supports rapid decision making. The results from a case study demonstrate the merit of the method. Several metamodeling techniques are compared and bootstrap error analysis and predicted residual sums of squares statistic are discussed to evaluate the standard error and error due to bias.
Importance of individual events in temporal networks

Records of time-stamped social interactions between pairs of individuals (e.g. face-to-face conversations, e-mail exchanges and phone calls) constitute a so-called temporal network. A remarkable difference between temporal networks and conventional static networks is that time-stamped events rather than links are the unit elements generating the collective behavior of nodes. We propose an importance measure for single interaction events. By generalizing the concept of the advance of events proposed by Kossinets et al (2008 Proc. 14th ACM SIGKDD Int. Conf. on Knowledge Discovery and Data Mining p 435), we propose that an event is central when it carries new information about others to the two nodes involved in the event. We find that the proposed measure properly quantifies the importance of events in connecting nodes along time-ordered paths. Because of strong heterogeneity in the importance of events present in real data, a small fraction of highly important events is necessary and sufficient to sustain the connectivity of temporal networks. Nevertheless, in contrast to the behavior of scale-free networks against link removal, this property mainly results from bursty activity patterns and not heterogeneous degree distributions.
Structure Preserving Algorithms for Perplectic Eigenproblems

Structured real canonical forms for matrices in R n×n that are symmetric or skew- symmetric about the anti-diagonal as well as the main diagonal are presented, and Jacobi algorithms for solving the complete eigenproblem for three of these four classes of matrices are developed. Based on the direct solution of 4× 4 subproblems constructed via quaternions, the algorithms cal- culate structured orthogonal bases for the invariant subspaces of the associated matrix. In addition to preserving structure, these methods are inherently parallelizable, numerically stable, and show asymptotic quadratic convergence.
Endoscopic video-assisted breast surgery: procedures and short-term results.

BACKGROUND We devised a new endoscopic operation for breast diseases. We report the aesthetic and treatment results of this procedure. METHODS A 2.5-cm axillary skin incision was made for a single approaching port, and a working space was created by retraction. Under video assistance, we resected the mammary gland partially or totally, and in the case of malignant diseases we also performed a sentinel lymph node biopsy and dissected axillary lymph nodes (levels I and II). RESULTS From December 2001 through April 2005, we performed endoscopic video-assisted breast surgery (VABS) in 100 patients with breast diseases. The diseases were benign in 18 patients and malignant in 82 patients. Of the malignant diseases, 80 underwent breast-conserving surgery and 2 underwent skin-sparing mastectomy. There was no significant difference in operation time, blood loss, or blood examinations related with the acute phase reaction between VABS and conventional breast-conserving procedures. All surgical margins were negative on examination of permanent histological preparations. The wounds healed without noticeable scarring. The original shapes of the breast were preserved. All patients expressed their great satisfaction with VABS. CONCLUSIONS VABS can be considered as a surgical option and can provide aesthetic advantages for patients with breast disease.
Goals Set in the Land of the Living/Dying: A Longitudinal Study of Patients Living with Advanced Cancer

A longitudinal qualitative research study was undertaken to provide an understanding of a prolonged experience of advanced cancer, as seen through the eyes of dying individuals. Using a variant of the grounded theory method, the authors theoretically sampled, from outpatient clinics in a large comprehensive cancer treatment center, 27 patients with either advanced lung or gastrointestinal cancer who had an expected survival of up to 2 years. The authors conducted a total of 54 interviews with these patients to learn of their experience of advanced cancer. The authors represent their experience with the core category: striving to grow in the land of the living/dying, symbolizing their sense of finding themselves in a borderland between life and death where their efforts focused on 3 common goals: controlling dying, valuing life in the present, and creating a living legacy. They provide a longitudinal account of how these goals were addressed throughout the illness trajectory and discuss the theoretical and clinical implications of this understanding for the experience of dying from advanced cancer.
Thiazolidinedione use and ulcerative colitis‐related flares: An exploratory analysis of administrative data

Background: Recent animal studies and clinical trials suggest that thiazolidinediones, a class of oral antidiabetic agents, are efficacious in reducing inflammation, yet no studies have evaluated their effectiveness in preventing flares. We examined the association between thiazolidinedione use and ulcerative colitis (UC)‐related flares. Methods: We conducted a retrospective cohort study using administrative data from 87 health plans across 33 states. Individuals with both UC and diabetes were identified using administrative definitions. Exposure to thiazolidinediones or other oral antidiabetic agents was ascertained through outpatient pharmacy claims. The primary outcome was occurrence of a UC flare defined by: 1) a new prescription for oral steroids, infliximab, or oral/rectal salicylates, or 2) a claim for colectomy. Secondary analyses analyzed outcomes separately. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression after matching each thiazolidinedione user to a comparable oral antidiabetic user on propensity score. Results: This study included 142 thiazolidinedione and 468 other oral antidiabetic users with a mean follow‐up of 7.3 and 6.2 months, respectively. Thiazolidinedione use was not associated with UC‐related flares as measured by the composite outcome (HR = 1.05, 95% CI: 0.66, 1.68). However, thiazolidinedione use was associated with a nonsignificant reduction in risk of oral steroid use when analyzed as a separate outcome (HR = 0.53, 95% CI: 0.20, 1.44). Conclusions: Thiazolidinediones do not provide any benefit over other oral antidiabetics in preventing UC‐related flares as measured by our primary composite outcome. However, thiazolidinedione use may reduce the risk of more significant disease flares requiring oral steroid treatment. (Inflamm Bowel Dis 2011;)
Why People Watch Reality TV

We assessed the appeal of reality TV by asking 239 adults to rate themselves on each of 16 basic motives using the Reiss Profile standardized instrument and to rate how much they watched and enjoyed various reality television shows. The results suggested that the people who watched reality television had above-average trait motivation to feel self-important and, to a lesser extent, vindicated, friendly, free of morality, secure, and romantic, as compared with large normative samples. The results, which were dose-dependent, showed a new method for studying media. This method is based on evidence that people have the potential to experience 16 different joys. People prefer television shows that stimulate the feelings they intrinsically value the most, which depends on individuality.
Alteration of somatosensory response in adulthood by early life stress

Early life stress is well-known as a critical risk factor for mental and cognitive disorders in adulthood. Such disorders are accompanied by altered neuro- (synapto-) genesis and gene expression. Because psychosomatic disorders induced by early life stress (e.g., physical and/or sexual abuse, and neglect) have become a socio-economic problem, it is very important to clarify the mechanisms underlying these changes. However, despite of intensive clinical and animal studies, such mechanisms have not yet been clarified. Although the disturbance of glucocorticoid and glutamate homeostasis by stress has been well-documented, it has not yet been clarified whether such disturbance by early life stress persists for life. Furthermore, since previous studies have focused on the detection of changes in specific brain regions, such as the hippocampus and prefrontal cortex, it has not been clarified whether early life stress induced changes in the sensory/motor system. Thus, in this review, we introduce recent studies on functional/structural changes in the somatosensory cortex induced by early life stress. We believe that this review provides new insights into the functional alteration of the somatosensory system induced by early life stress. Such information may have clinical relevance in terms of providing effective therapeutic interventions to early life stressed individuals.
Paradoxical Low-Flow, Low-Gradient Severe Aortic Stenosis Despite Preserved Ejection Fraction Is Associated With Higher Afterload and Reduced Survival

Background— Recent studies and current clinical observations suggest that some patients with severe aortic stenosis on the basis of aortic valve area may paradoxically have a relatively low gradient despite the presence of a preserved left ventricular (LV) ejection fraction. The objective of the present study was to document the prevalence, potential mechanisms, and clinical relevance of this phenomenon. Methods and Results— We retrospectively studied the clinical and Doppler echocardiographic data of 512 consecutive patients with severe aortic stenosis (indexed aortic valve area ≤0.6 cm2 · m−2) and preserved LV ejection fraction (≥50%). Of these patients, 331 (65%) had normal LV flow output defined as a stroke volume index >35 mL · m2, and 181 (35%) had paradoxically low-flow output defined as stroke volume index ≤35 mL · m−2. When compared with normal flow patients, low-flow patients had a higher prevalence of female gender (P<0.05), a lower transvalvular gradient (32±17 versus 40±15 mm Hg; P<0.001), a lower LV diastolic volume index (52±12 versus 59±13 mL · m−2; P<0.001), lower LV ejection fraction (62±8% versus 68±7%; P<0.001), a higher level of LV global afterload reflected by a higher valvulo-arterial impedance (5.3±1.3 versus 4.1±0.7 mm Hg · mL−1 · m−2; P<0.001) and a lower overall 3-year survival (76% versus 86%; P=0.006). Only age (hazard ratio, 1.04; 95% CI, 1.01 to 1.08; P=0.025), valvulo-arterial impedance >5.5 mm Hg · mL−1 · m−2 (hazard ratio, 2.6; 95% CI, 1.2 to 5.7; P=0.017), and medical treatment (hazard ratio, 3.3; 95% CI, 1.8 to 6.7; P=0.0003) were independently associated with increased mortality. Conclusion— Patients with severe aortic stenosis may have low transvalvular flow and low gradients despite normal LV ejection fraction. A comprehensive evaluation shows that this pattern is in fact consistent with a more advanced stage of the disease and has a poorer prognosis. Such findings are clinically relevant because this condition may often be misdiagnosed, which leads to a neglect and/or an underestimation of symptoms and an inappropriate delay of aortic valve replacement surgery.
Salivary cortisol and testosterone responses to high-intensity cycling before and after an 11-day intensified training period

Abstract This study examined salivary cortisol and testosterone responses to two, different high-intensity, ∼30-min cycles separated by 2 h rest before and after an 11-day intensified training period. Twelve recreationally active, healthy males completed the study. Saliva samples were collected before, immediately after and 30 min after both bouts with salivary cortisol and testosterone concentrations assessed. Compared with pre-training blunted exercise-induced salivary cortisol, testosterone and cortisol/testosterone responses to both bouts post-training were observed (P < 0.05 for all). Comparing pre- with post-training the absolute exercise-induced salivary cortisol, testosterone and cortisol/testosterone decreased from 11.1 to 3.1 and 7.0 to 4.4 nmol · L−1 (cortisol), from 407 to 258 and from 473 to 274 pmol · L−1 (testosterone) and from 12 to 4 and 7 to 5 (cortisol/testosterone) for the first and second bouts, respectively (P < 0.05). No differences in the pre- and post-training rating of perceived exertion (RPE) and heart rate (HR) responses during the cycles or times to fatigue were found (P > 0.05). Fatigue and Burnout scores were higher post- compared with pre-training (P < 0.05). These high-intensity exercise bouts can detect altered hormonal responses following intensified training. This test could assess an athlete's current hormonal status, reductions in salivary cortisol and testosterone responses suggestive of increased fatigue.
Iterative design of an interface for easy 3-D direct manipulation

Although computer tools for 3-D design applications are now widely available for use on personal computers, they are unnecessarily difficult to use. Conventions for establishing and manipulating views of 3-D objects require engineering-oriented dialogues that are foreign to most users. This paper describes the iterative design and testing of a new mechanism for moving 3-D objects with a mouse-controlled cursor in a space planning application prototype. Emphasis was placed on developing a design which would make 3-D interaction more intuitive by preserving users' experiences with moving objects in the real, physical world. Results of an informal user test of the current interface prototype are presented and implications for the development of a more general direct manipulation mechanism are discussed.
Finding Sparse Features for Face Detection Using Genetic Algorithms

Although Face detection is not a recent activity in the field of image processing, it is still an open area for research. The greatest step in this field is the work reported by Viola and the recent analogous one is proposed by Huang et al. Both of them use similar features and also similar training process. The former is just for detecting upright faces, but the latter can detect multi-view faces in still grayscale images using new features called 'sparse feature'. Finding these features is very time consuming and inefficient by proposed methods. Here, we propose a new approach for finding sparse features using a genetic algorithm system. This method requires less computational cost and gets more effective features in learning process for face detection that causes more accuracy.
Coreceptor Signal Strength Regulates Positive Selection but Does Not Determine CD4/CD8 Lineage Choice in a Physiologic In Vivo Model1

TCR signals drive thymocyte development, but it remains controversial what impact, if any, the intensity of those signals have on T cell differentiation in the thymus. In this study, we assess the impact of CD8 coreceptor signal strength on positive selection and CD4/CD8 lineage choice using novel gene knockin mice in which the endogenous CD8α gene has been re-engineered to encode the stronger signaling cytoplasmic tail of CD4, with the re-engineered CD8α gene referred to as CD8.4. We found that stronger signaling CD8.4 coreceptors specifically improved the efficiency of CD8-dependent positive selection and quantitatively increased the number of MHC class I (MHC-I)-specific thymocytes signaled to differentiate into CD8+ T cells, even for thymocytes expressing a single, transgenic TCR. Importantly, however, stronger signaling CD8.4 coreceptors did not alter the CD8 lineage choice of any MHC-I-specific thymocytes, even MHC-I-specific thymocytes expressing the high-affinity F5 transgenic TCR. This study documents in a physiologic in vivo model that coreceptor signal strength alters TCR-signaling thresholds for positive selection and so is a major determinant of the CD4:CD8 ratio, but it does not influence CD4/CD8 lineage choice.
Face Recognition Based on Randomized Subspace Feature

Kernel Principal Component Analysis (KPCA) is a popular feature extraction technique for face recognition. However, it often suffers from the high computational complexity problem, when dealing with large samples. Besides, KPCA is a holistic feature based approach, which means that it discards some useful discriminate local information. In this paper, we use Random Nonlinear Principal Component Analysis (RNPCA) and extract Local Ternary Patterns (LTP) features to improve them respectively. We calculate the kernel matrix by constructing random Fourier features, thus the computation efficiency is speeded up. The LTP features are also extracted, so the local texture information is preserved. In the classification section, we use distance metric learning to improve the classification ability of nearest neighbors classifier. Experimental results on AR, FERET, Yale, ORL face databases demonstrated the effectiveness of our method.
Polynomial association rules with applications to logistic regression

A new class of associations (polynomial itemsets and polynomial association rules) is presented which allows for discovering nonlinear relationships between numeric attributes without discretization. For binary attributes, proposed associations reduce to classic itemsets and association rules. Many standard association rule mining algorithms can be adapted to finding polynomial itemsets and association rules. We applied polynomial associations to add non-linear terms to logistic regression models. Significant performance improvement was achieved over stepwise methods, traditionally used in statistics, with comparable accuracy.
Iterative Decision-Directed Joint Frequency Offset and Channel Estimation for KSP-OFDM

We propose an iterative decision-directed joint frequency offset (FO) and channel estimation algorithm in a known symbol padding (KSP) orthogonal frequency division multiplexing (OFDM) system, where the guard interval is filled with pilot symbols. Besides those time domain pilot symbols, some additional pilot symbols are transmitted on the pilot carriers. The decision-directed algorithm is initialized by pilot-aided FO estimation without channel knowledge. We propose a possible initialization algorithm that operates in the frequency domain (FD). After the initialization phase, the iterative decision-directed estimation algorithm is applied. For the channel estimation step, an existing pilot-aided channel estimation algorithm is extended to a decision-directed algorithm which uses the Fast Fourier Transform outputs at both the pilot and data carrier positions. For the uncoded case, the proposed iterative decision-directed joint FO and channel estimation algorithm reaches the bit error rate performance of a receiver with perfect synchronization and perfect channel knowledge. For a coded system, there is small loss in performance of less than 1 dB when our proposed algorithm is applied compared to a receiver with perfect knowledge about the FO and the channel.
Comparison of spinal cord gray matter and white matter softness: measurement by pipette aspiration method.

OBJECT Although the gray matter of the spinal cord has been thought to be softer than the white matter, there is no evidence to support this belief. Because the spinal cord is extremely soft, it has been difficult to measure the mechanical properties of the gray and white matter. The modulis of elasticity of the gray and white matter were measured in situ by using a pipette aspiration method. METHOD The spinal cord specimens were excised from Japanese white rabbits. Specimens were cut to display the surfaces of axial, frontal, and sagittal sections. The surfaces of the gray and white matter were aspirated using a 0.8-mm-inner-diameter glass pipette while monitoring with a video microscope, and the deformed length in the pipette was measured on a monitor. In each case the modulus of elasticity was calculated by comparing the relationship between the aspiration pressure and aspirated volume of the specimen with that determined by finite element analysis. The moduli of elasticity of the gray and white matter were 3.4+/-1.4 kPa (mean +/- standard deviation) and 3.4+/-0.9 kPa in the axial section, 3+/-0.3 kPa and 3.5+/-0.5 kPa in the frontal section, and 3.5+/-0.9 kPa and 2.8+/-0.4 kPa in the sagittal section, respectively. CONCLUSIONS No significant difference in modulus of elasticity was shown between the gray and white matter of the spinal in sections made in various directions.