Miracle-dz/UniFAR-FTUs huggingface dataset:
Scavenging of Peroxynitrite Reduces Renal Ischemia/Reperfusion Injury

Introduction. Nitric oxide (NO) and peroxynitrite (OONO—) are implicated in the pathophysiology of renal ischemia/reperfusion (I/R). The aim of this study was to investigate and compare the efficiency of S-methylisothiourea (SMT), an iNOS inhibitor, and mercaptoethylguanidine (MEG), a scavenger of peroxynitrite, on renal dysfunction and injury induced by I/R of rat kidney. Materials and Methods. Thirty-two male Sprague-Dawley rats were divided into four groups: sham-operated, I/R, I/R+SMT, and I/R+MEG. Rats were given SMT (10 mg/kg ip) or MEG (10 mg/kg ip) 6 h prior to I/R and at the beginning of reperfusion. All rats except sham-operated underwent 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood were obtained for evaluation. Superoxide dismutase, glutathione peroxidase, malondialdehide, protein carbonyl content, and nitrite/nitrate level (NOx) were determined in the renal tissue. Serum creatinine (SCr), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) were determined in the blood. Additionally, renal sections were used for histological grade of renal injury. Results. SMT and MEG significantly reduced the I/R-induced increases in SCr, BUN, and AST. Both SMT and MEG attenuated the tissue NOx levels, indicating reduced NO production. In addition, SMT and MEG markedly reduced elevated oxidative stress product, restored decreased antioxidant enzymes, and attenuated histological alterations. Interestingly, MEG exerted a greater renoprotective effect than SMT. Conclusions. These data support the finding that iNOS and peroxynitrite are involved in the renal I/R injury, and suggest that a scavenger of peroxynitrite might be more effective than iNOS inhibitors as a therapeutic intervention.
Application of Micropillar Interfaces: A Study on Human Periodontal Cells and Actin Biomimetic Systems

Microstructured interfaces such as micropillars made of polydimethyl-siloxane (PDMS) provide a novel approach both as topologically defined, force sensing substrates in cell culture as well as scaffolds for biomimetic protein assays. This work is divided into two parts. In the first part, PDMS micropillar arrays functionalized with fibronectin, are applied as a biomechanical microenvironment for immortalized human gingival keratinocytes (IHGKs) and gingival connective-tissue fibroblasts (GCTFs). IHGKs and GCTFs show successful adhesion and growth on the pillar heads and exert forces up to about 110 nN in the case of IHGKs and about 174 nN for GCTFs. Varying the interpillar distances affects the early keratinocyte differentiation and morphology. At decreasing inter-pillar distances the IHGKs show an increased keratin 1 (K1) extension in the cytoplasm, increased mRNA transcription of keratin 1 and a shape change from a more linear to a more round form. A novel GCTF-IHGK co-culture system is developed as a model of the epithelial tissue, to study explicitly the role of the GCTFs in the morphogenesis of the derived epithelial equivalents. The epithelial equivalents, cultured for 7 and 14 days on GCTF-populated pillar arrays, are found more similar to the in vivo phenotype than the GCTF-free cultures. These findings are confirmed by following the mRNA transcription levels for keratin 1. A novel, transparent microfluidic platform, based on PDMS pillars is developed in the second part of this work. It is designed to investigate actin cortex models and to provide control over the physicochemical environment, allowing simultaneous high resolution fluorescence microscopy. The formation of crosslinking networks is observed using various crosslinkers, such as filamin, myosin II, alpha-actinin and magnesium ions. Dependent of the geometric configuration of the actin filaments anchored to the pillar tops, so-called zipping crosslinks are observed. The zipping velocity is both influenced by the flow speed, as well as the number and the configuration of the filaments involved in the process. It is found to range between 2 - 15 µm/s. To further quantify the crosslinking process, the flow-cell is combined with an optical tweezers system. The unzipping forces are measured for the crosslinkers alpha-actinin and magnesium ions. Forces of about 17 - 20 pN are derived for magnesium ions and about 30-45 pN for alpha-actinin.
Sensory gating in the human hippocampal and rhinal regions: Regional differences

To further explore the roles of medial temporal structures in mediating sensory gating of incoming irrelevant or redundant auditory input, twenty‐seven patients with intractable epilepsy with depth electrodes implanted in the medial temporal lobe for presurgery evaluation underwent evoked response recording to auditory paired‐stimuli (S1–S2). Seventeen subjects were diagnosed with left medial temporal lobe epilepsy (MTLE) and 10 with right MTLE. Only data from the nonlesion side were included. Twenty‐three records from rhinal and anterior hippocampal regions, and 21 from posterior hippocampal regions were included in the analysis. The rhinal region had two prominent components (a negativity peaking around 200 ms followed by a positivity peaking around 400 ms). Both the anterior and posterior hippocampal regions exhibited a dominant negative potential peaking around 400 ms. These components were all composed predominantly of slower frequencies. In contrast, a negativity in the posterior hippocampus at around 100 ms was composed of slow and fast frequencies. All components but the early rhinal negativity were attenuated by stimulus repetition. This is the first report documenting that different regions of the medial temporal area are differentially involved in the processing of auditory input, most likely reflecting separate steps of processing. The data support the need for further exploration of the contribution of these regions to sensory gating. This information helps to increase our understanding of this basic but important and complex function. © 2007 Wiley‐Liss, Inc.
Power amplifier characterization: an active load-pull system based on six-port reflectometer using complex modulated carrier

An original measurement system for nonlinear RF power-transistor characterization is presented. This new setup enables measurement and optimization of output power, power-added efficiency (PAE), or linearity using active fundamental tuning and six-port reflectometers as vector network analyzers. High- and low-frequency bias-tees are inserted at both ports of transistors in order to control source and load impedances at the baseband (envelope) frequency. Experimental results at 1.575 GHz show an adjacent channel power ratio improvement of 20 dB for a commercial GaAs MESFET power transistor operating in class AB. Moreover, the output power and PAE are increased by 1 dB and ten points, respectively
Complexity and quality evaluation of structure extrapolation methods within a fully automatic inpainting framework

A novel, automatic restoration framework of large picture areas is proposed in this paper. While the damaged picture areas may have been caused by accident or transmission loss, the challenge consists in repairing the occluded or missing image regions in an undetectable way. In this work, the new inpainting method is used as framework for systematic evaluation of relevant structure extrapolation strategies. The important issue of quality-complexity optimization is thoroughly discussed and efficient inpainting tools are established. Recovery of missing dominant structures is done via tensor voting, regression analysis or a combination of both. Combined structure extrapolation considerably reduces the complexity of structure restoration, compared to genuine tensor voting, with overall graceful to imperceptible degradation of the inpainting result. Furthermore, limitations of the tensor voting approach can be avoided by means of polynomial interpolation with additional savings in terms of complexity.
Breast neoplasms: T2* susceptibility-contrast, first-pass perfusion MR imaging.

PURPOSE To evaluate the differentiation of benign from malignant breast tumors with T2*-weighted perfusion magnetic resonance (MR) imaging (blood volume imaging) versus that with dynamic T1-weighted contrast agent-enhanced MR imaging. MATERIALS AND METHODS Ten healthy adult volunteers and 18 adult patients with benign or malignant lesions underwent both conventional T1-weighted dynamic contrast-enhanced breast MR imaging and repetitive first-pass, single-section, dynamic T2*-weighted perfusion MR imaging. Images were obtained before, during, and after injection of 20 mL of gadopentetate dimeglumine; peak gadopentetate dimeglumine concentrations were calculated from the maximal signal intensity loss on T2*-weighted images. RESULTS No perfusion effect was detectable in healthy breast parenchyma. A strong susceptibility-mediated signal intensity loss occurred in malignant breast tumors. No or only minor perfusion effects were seen in fibroadenomas, in spite of their rapid enhancement at T1-weighted dynamic imaging. Perfusion imaging was possible after conventional dynamic contrast-enhanced breast MR imaging. CONCLUSION T2*-weighted perfusion imaging exploits the susceptibility-mediated signal intensity loss of a first-pass bolus of gadopentetate dimeglumine within the capillary bed. First-pass perfusion imaging of breast lesions is feasible. It is promising in the differentiation of benign from malignant, rapidly enhancing lesions.
Evaluation of the Prevalence Rate and the Prognostic Effect of Human Papilloma Virus Infection in a Group of Patients With Oral Cavity Squamous Cell Carcinoma

Background Squamous cell carcinoma (SCC) is the most common malignancy of the oral cavity. A relationship between the human papilloma virus (HPV) infection and the prognosis of oral cavity SCC (OCSCC) has been discussed before. Objectives We investigated the prevalence rate of HPV status in patients with OCSCC, and its effects on clinicopathological characteristics of tumors and patients’ prognosis. Patients and Methods Sections of formalin-fixed, paraffin-embedded tissue blocks from 114 histopathologically confirmed OCSCC cases were investigated in this study. Polymerase chain reaction (PCR) was applied to evaluate the HPV status in the samples. Results Fifteen (13.16%) cases were identified as HPV positive. The detected viral subtypes in this study were the subtypes 6 and 11. The stage and especially lymph node stage was significantly higher in the HPV positive group compared to the HPV negative group (P = 0.04). Disease free survival (DFS) was remarkably lower in the HPV positive group compared to the HPV negative group (13.9 vs. 49.9 months, P = 0.02). Overall survival (OS) was also significantly inferior in the HPV positive group (15.7 vs. 49.6 months, P = 0.01). In the current study, no significant differences were observed between two groups in relation to the variables of age, gender, tumors site, tumor size, tumor grading and also the recurrence rate. Conclusions The observed higher mortality rate among the HPV positive group indicates the poorer prognosis of this group in comparison with the HPV negative patients. The incidence rate of HPV infection was low in the studied samples; however, interaction of subtypes 6 and 11 of HPV in poorer prognosis of the patients and a carcinogenic role of HPV in OCSCC cannot be ruled out.
Sharing graphs using differentially private graph models

Continuing success of research on social and computer networks requires open access to realistic measurement datasets. While these datasets can be shared, generally in the form of social or Internet graphs, doing so often risks exposing sensitive user data to the public. Unfortunately, current techniques to improve privacy on graphs only target specific attacks, and have been proven to be vulnerable against powerful de-anonymization attacks. Our work seeks a solution to share meaningful graph datasets while preserving privacy. We observe a clear tension between strength of privacy protection and maintaining structural similarity to the original graph. To navigate the tradeoff, we develop a differentially-private graph model we call Pygmalion. Given a graph G and a desired level of e-differential privacy guarantee, Pygmalion extracts a graph's detailed structure into degree correlation statistics, introduces noise into the resulting dataset, and generates a synthetic graph G'. G' maintains as much structural similarity to G as possible, while introducing enough differences to provide the desired privacy guarantee. We show that simply applying differential privacy to graphs results in the addition of significant noise that may disrupt graph structure, making it unsuitable for experimental study. Instead, we introduce a partitioning approach that provides identical privacy guarantees using much less noise. Applied to real graphs, this technique requires an order of magnitude less noise for the same privacy guarantees. Finally, we apply our graph model to Internet, web, and Facebook social graphs, and show that it produces synthetic graphs that closely match the originals in both graph structure metrics and behavior in application-level tests.
Variation in Specialists’ Reported Hospitalization Practices of Children Sustaining Blunt Abdominal Trauma

Introduction Children with blunt abdominal trauma (BAT) are often hospitalized despite no intervention. We identified factors associated with emergency department (ED) disposition of children with BAT and differing computed tomography (CT) findings. Methods: We surveyed pediatric and general emergency physicians (EPs), pediatric and trauma surgeons regarding care of 2 hypothetical asymptomatic patients: a 9-year-old struck by a slow-moving car (Case 1) and an 11-month-old who fell 10 feet (Case 2). We presented various abdominal CT findings and asked physicians about disposition preferences. We evaluated predictors of patient discharge using multivariable regression analysis, adjusting for hospital and ED characteristics, and clinician experience. Pediatric EPs served as the reference group. Results: Of 2,003 eligible surveyed, 636 (32%) responded. For normal CTs, 99% would discharge in Case 1 and 88% in Case 2. Prominent specialty differences included: for trace intraperitoneal fluid (TIF), 68% would discharge in Case 1 and 57% in Case 2. Patients with TIF were less likely to be discharged by pediatric surgeons (Case 1: OR 0.52, 95% CI 0.32, 0.82; Case 2: OR 0.49, 95% CI 0.30, 0.79). Patients with renal contusions were less likely to be discharged by pediatric surgeons (Case 1: OR 0.55, 95% CI 0.32, 0.95) and more likely by general EPs (Case 1: OR 1.83, 95% CI 1.25, 2.69; Case 2: OR 2.37, 95% CI 1.14, 4.89). Conclusion: Substantial variation exists between specialties in reported hospitalization practices of asymptomatic children after abdominal trauma with minor CT findings. Better evidence is needed to guide disposition decisions.
Hemodynamic Significance of High Brachial Pulse Pressure in Young Men

This study investigates whether an increased brachial pulse pressure (PP) in young healthy men constitutes a representative measure of the central hemodynamic forces, or the mere expression of an exaggerated upper limb amplification. Thirty two healthy men between 17 and 28 years old underwent noninvasive evaluation of systemic hemodynamics (impedance cardiography) and pulse wave analysis (SphygmoCor). Subjects were divided into 3 predefined groups of brachial PP: < 50, 50–64, and ≥ 65 mmHg. The brachial–central PP difference increased with increasing brachial PP (17 ± 4, 22 ± 4, and 29 ± 4 mmHg, respectively P < 0.001). In contrast, peripheral amplification (as measured by the brachial:central PP ratio) remained constant among the tree groups, at the expense of a concomitant widening of aortic PP (P < 0.001) without difference in augmentation index. In the entire sample, central and brachial PP, and the difference between the two measures, correlated positively with cardiac output (P < 0.001) and stroke volume (P < 0.01), and negatively with systemic vascular resistance (P < 0.001), without significant relationship with heart rate. In conclusion, despite the different amplitude, central and brachial PP shared common hemodynamic determinants. A high PP among young men underlied a high output‐low resistance circulatory pattern, independently of the site of measurement
Semiparametric Estimation and Inference Using Doubly Robust Moment Conditions

We study semiparametric two-step estimators which have the same structure as parametric doubly robust estimators in their second step, but retain a fully nonparametric specification in the first step. Such estimators exist in many economic applications, including a wide range of missing data and treatment effect models. We show that these estimators are ? n-consistent and asymptotically normal under weaker than usual conditions on the accuracy of the first stage estimates, have smaller first order bias and second order variance, and that their finite-sample distribution can be approximated more accurately by classical first order asymptotics. We argue that because of these refinements our estimators are useful in many settings where semiparametric estimation and inference are traditionally believed to be unreliable. We also illustrate the practical relevance of our approach through simulations and an empirical application.
Specular Flow and Shape in One Shot:

An image of a purely specular object is just a distortion of its surrounding illumination environment. Therefore, when only little (or nothing) about the illumination environment is known, inferring the geometrical structure of specular objects is a very challenging task. Nevertheless, recent studies have addressed this problem by exploiting relative motion between the observed object, the camera and the environment (e.g.,[1, 4]). In the image plane such motion induces a specular flow – the optical flow of observed specular reflections – which has been shown to be independent of environment content and therefore to facilitate shape reconstruction. The shape-from-specular-flow (SFSF) approach follows the intuitive hierarchical thinking: First, estimate the relevant (specular) flow in the image plane. Next, exploit it for (specular) shape recovery by solving the SFSF equation ([1]). The SFSF equation expresses the relationship between the specular flow, the shape of the specular object, and its motion relative to the environment. A linear form for the SFSF equation have been formulated in [4] assuming that the unknown specular object is represented via the field of its reflection vectors, r∈ S2. In this case the SFSF equation becomes ∂r(x) ∂x u(x) = ω× r(x), (1)
The student-t mixture as a natural image patch prior with application to image compression

Recent results have shown that Gaussian mixture models (GMMs) are remarkably good at density modeling of natural image patches, especially given their simplicity. In terms of log likelihood on real-valued data they are comparable with the best performing techniques published, easily outperforming more advanced ones, such as deep belief networks. They can be applied to various image processing tasks, such as image denoising, deblurring and inpainting, where they improve on other generic prior methods, such as sparse coding and field of experts. Based on this we propose the use of another, even richer mixture model based image prior: the Student-t mixture model (STM). We demonstrate that it convincingly surpasses GMMs in terms of log likelihood, achieving performance competitive with the state of the art in image patch modeling. We apply both the GMM and STM to the task of lossy and lossless image compression, and propose efficient coding schemes that can easily be extended to other unsupervised machine learning models. Finally, we show that the suggested techniques outperform JPEG, with results comparable to or better than JPEG 2000.
Improved pulse detection from head motions using DCT

The heart pulsation sends out the blood throughout the body. The rate in which the heart performs this vital task, heartbeat rate, is of curial importance to the body. Therefore, measuring heartbeat rate, a.k. a. pulse detection, is very important in many applications, especially the medical ones. To measure it, physicians traditionally, either sense the pulsations of some blood vessels or install some sensors on the body. In either case, there is a need for a physical contact between the sensor and the body to obtain the heartbeat rate. This might not be always feasible, for example, for applications like remote patient monitoring. In such cases, contactless sensors, mostly based on computer vision techniques, are emerging as interesting alternatives. This paper proposes such a system, in which the heartbeats (pulses) are detected by subtle motions that appear on the face due to blood circulation. The proposed system has been tested in different facial expressions. The experimental results show that the proposed system is correct and robust and outperforms state-of-the-art.
Complex Locking Rather Than Complete Cessation of Neuronal Activity in the Globus Pallidus of a 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine-Treated Primate in Response to Pallidal Microstimulation

High-frequency stimulation of the globus pallidus (GP) has emerged as a successful tool for treating Parkinson's disease and other motor disorders. However, the mechanism governing its therapeutic effect is still under debate. To shed light on the basic mechanism of deep brain stimulation (DBS), we performed microstimulation in the GP of a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated monkey while recording with other microelectrodes in the same nucleus. We used robust methods to reduce the stimulus artifact, and 600-3000 repetitions of a single stimulus and of high-frequency short trains (10-40 stimuli), enabling high temporal resolution analysis of neural responses. Low-frequency stimulation yielded a typical three-stage response: short-term (2-3 msec duration) activity, followed by mid-term (15-25 msec) inhibition, and occasionally longer-term (30-40 msec) excitation. Trains of high-frequency stimuli elicited complex locking of the response to the stimuli in most neurons. The locking displayed a stereotypic temporal structure consisting of three short-duration (1-2 msec) phases: an initial (mean latency = 2.9 msec) excitation followed by an inhibition (4.6 msec) and a second excitation (6.3 msec). The change in the mean firing rate was mixed; the majority of the neurons displayed partial inhibition during the stimulus train. Slow inhibitory and excitatory multiphase changes in the firing rate were observed after the stimulus trains. The activity of neurons recorded simultaneously displayed rate correlations but no spike-to-spike correlations. Our results suggest that the effect of DBS on the GP is not complete inhibition but rather a complex reshaping of the temporal structure of the neuronal activity within that nucleus.