Miracle-dz/UniFAR-FTUs huggingface dataset:
75 Determining Soil Hydraulic Properties

Hydraulic properties are required for modeling water and solute transport in unsaturated soils. The bottleneck for the successful application of numerical simulation models lays usually in their parameter estimation requirements. Methods to determine hydraulic properties can be classified into indirect and direct approaches. Indirect methods encompass the estimation of hydraulic properties by pedotransfer functions from more easily measured soil properties, and the prediction of the unsaturated hydraulic conductivity function from the water retention curve (WRC). In direct methods, observations offlow attributes from laboratory or field experiments are evaluated. This article reviews common methods to estimate the hydraulic conductivity function from the water retention characteristic and various direct measurement techniques in the laboratory and the field. We conclude with an outlook on contemporary developments in measurement techniques, stressing the key role of inverse modeling of experiments to derive optimum hydraulic properties and the importance of a future combination of noninvasive measurement techniques with inverse modeling by stochastic data fusion.
Combustion Processes in Hybrid Rocket Engines

In recent years, there has been a resurgence of interest in the development of hybrid rocket engines for advanced launch vehicle applications. Hybrid propulsion systems use a solid fuel such as hydroxyl-terminated polybutadiene (HTPB) along with a gaseous/liquid oxidizer. The performance of hybrid combustors depends on the convective and radiative heat fluxes to the fuel surface, the rate of pyrolysis in the solid phase, and the turbulent combustion processes in the gaseous phases. These processes in combination specify the regression rates of the fuel surface and thereby the utilization efficiency of the fuel. In this paper, we employ computational fluid dynamics (CFD) techniques in order to gain a quantitative understanding of the physical trends in hybrid rocket combustors. The computational modeling is tailored to ongoing experiments at Penn State that employ a two dimensional slab burner configuration. The coordinated computational/experimental effort enables model validation while providing an understanding of the experimental observations. Computations to date have included the full length geometry with and with the aft nozzle section as well as shorter length domains for extensive parametric characterization. HTPB is sed as the fuel with 1,3 butadiene being taken as the gaseous product of the pyrolysis. Pure gaseous oxygen is taken as the oxidizer. The fuel regression rate is specified using an Arrhenius rate reaction, which the fuel surface temperature is given by an energy balance involving gas-phase convection and radiation as well as thermal conduction in the solid-phase. For the gas-phase combustion, a two step global reaction is used. The standard kappa - epsilon model is used for turbulence closure. Radiation is presently treated using a simple diffusion approximation which is valid for large optical path lengths, representative of radiation from soot particles. Computational results are obtained to determine the trends in the fuel burning or regression rates as a function of the head-end oxidizer mass flux, G=rho(e)U(e), and the chamber pressure. Furthermore, computation of the full slab burner configuration has also been obtained for various stages of the burn. Comparisons with available experimental data from small scale tests conducted by General Dynamics-Thiokol-Rocketdyne suggest reasonable agreement in the predicted regression rates. Future work will include: (1) a model for soot generation in the flame for more quantitative radiative transfer modelling, (2) a parametric study of combustion efficiency, and (3) transient calculations to help determine the possible mechanisms responsible for combustion instability in hybrid rocket motors.
Dielectric relaxation and electronic structure of double perovskite Sr2FeSbO6

The dielectric property and the electronic structure of a double perovskite, Sr2FeSbO6 (SFS) synthesized by solid state reaction technique are investigated. The x-ray diffraction of the sample taken at room temperature shows cubic phase. The scanning electron micrograph of the sample also confirms the formation of the single phase of the material. We have measured the capacitance and conductance of SFS in a frequency range from 50 Hz to 1 MHz and in a temperature range from 163 to 463 K. A relaxation is observed in the entire temperature range as a gradual decrease in ϵ′(ω) and as a broad peak in ϵ″(ω). The frequency dependent electrical data are analyzed in the framework of conductivity and electric modulus formalisms. The frequencies corresponding to the maxima of the imaginary electric modulus at various temperatures are found to obey an Arrhenius law with an activation energy of 0.74 eV. The Cole–Cole model is used to study the dielectric relaxation of SFS. The scaling behavior of imaginary part of el.
Scanning tunneling spectroscopy at the single atom scale

This thesis reports measurements at the single atom scale by using low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS). Different sample systems where analyzed with normal conducting and superconducting tips. Chapter 2 presents the theoretical aspects which have to be taken into account for a detailed analysis and a consistent interpretation of the STS measurements. In chapter 3 the creation of a hexagonally ordered superlattice of single Ce adatoms on Ag(111) is reported and understood within a scattering model of the surface state electrons with the adatoms. Furthermore, the change in the local density of states of the surface state in ordered and slightly disordered superlattices is measured and theoretically explained within a tight-binding model which allows to understand the creation and stability of the superlattice by an energy gain of the participating surface-state electrons. Because Ce atoms have a non-vanishing magnetic moment which is expected to interact with the continuous states of the supporting surface leading to a Kondo resonance, chapter 4 presents measurements on single Ce adatoms on different Ag surfaces. This chapter shows the difficulties to interpret the obtained data. For instance, bistable Ce adatoms are detected on Ag(100) which show drastical changes in their apparent height and spectral signature depending on the tunneling conditions. The possible physical processes behind these phenomena are discussed. While the results presented in the first chapters were obtained with a normal conducting tip, chapter 5 intensively discusses the opportunities superconducting tips offer in low-temperature STS measurements. Novel insight in and thorough understanding of Andreev reflection processes are obtained by using the unique possibility of having different superconducting gaps in the tip and the sample. Detailed analyses of the supercurrent at low tunneling resistances reveal tunneling currents which are not described within the standard resistivity shunted junction model, and are presumably due to self-induced tunneling or due to an additional quasiparticle tunneling channel which only exist in asymmetric junctions. Furthermore, the influence of single magnetic Co atoms inbetween the superconducting tunnel junction on the obtained spectrum is discussed.
A Step to the Reionization Epoch

The reionization epoch may lie not far beyond the most distant known quasars and galaxies, and it might be detectable in a variety of ways. One possibility discussed here is to search for an all-sky spectral step produced by the redshifted HI that was present prior to reionization.
Dynamic Transitions in Neuronal Network Firing Sustained by Abnormal Astrocyte Feedback

Astrocytes play a crucial role in neuronal firing activity. Their abnormal state may lead to the pathological transition of neuronal firing patterns and even induce seizures. However, there is still little evidence explaining how the astrocyte network modulates seizures caused by structural abnormalities, such as gliosis. To explore the role of gliosis of the astrocyte network in epileptic seizures, we first established a direct astrocyte feedback neuronal network model on the basis of the hippocampal CA3 neuron-astrocyte model to simulate the condition of gliosis when astrocyte processes swell and the feedback to neurons increases in an abnormal state. We analyzed the firing pattern transitions of the neuronal network when astrocyte feedback starts to change via increases in both astrocyte feedback intensity and the connection probability of astrocytes to neurons in the network. The results show that as the connection probability and astrocyte feedback intensity increase, neuronal firing transforms from a nonepileptic synchronous firing state to an asynchronous firing state, and when astrocyte feedback starts to become abnormal, seizure-like firing becomes more severe and synchronized; meanwhile, the synchronization area continues to expand and eventually transforms into long-term seizure-like synchronous firing. Therefore, our results prove that astrocyte feedback can regulate the firing of the neuronal network, and when the astrocyte network develops gliosis, there will be an increase in the induction rate of epileptic seizures.
Governance of Cloud computing infrastructures using knowledge management / von Michael Maurer

Cloud computing has gained a lot of momentum in recent years. Its vision is to offer computing power as a utility implying sheerly unlimited and instantly provisioned resources for customers. However, there are a lot of obstacles towards these goals. This thesis tackles two of them related to Service Level Agreements (SLAs): adaptive SLA mapping, and resourceand energy-efficient SLA enactment. A Cloud provider who wants to offer computing resources signs an SLA with the customer. In this SLA the provider states the Quality of Service (QoS) she will guarantee, the price the customer will have to pay, and the penalty the provider will have to pay in case she breaches the QoS guarantees. The customer has his own SLA with the QoS guarantees he wants, and the prices he is willing to pay. Matching these bids and asks is especially hard as non-standardized varying definitions of computing resources in electronic markets cause a large variety of different SLAs. Moreover, these SLAs are typically bound to internal business processes and, therefore, cannot be altered easily. In this thesis we use SLA templates and SLA mappings that allow providers and customers to map parameters of their SLAs to each other without changing the original ones. From these mappings we learn user preferences and are able to generate and adapt public SLA templates that reflect the users’ needs and help to standardize SLAs. We present a cost-benefit analysis of this approach and evaluate various learning and adaptation strategies. Furthermore, after bids and asks have been matched and the SLA has been signed, the Cloud provider has to keep up to her promises to avoid SLA penalties – despite all the dynamism of workload changes. On the other hand, also under-utilization of resources and high energy wastage are big cost factors in large-scale distributed systems. Consequently, a Cloud provider aims at minimizing SLA violations, maximizing resource utilization, and minimizing energy wastage. However, this is not straightforward as Cloud computing infrastructures consist of many differently configurable elements as applications, virtual machines (VMs), physical machines (PMs), and also other Cloud providers, to which applications can be outsourced. This leads to a plethora of possible reconfiguration and reallocation actions of these elements and the resources they are assigned to. Many of the resulting problems are typically NP-hard. This thesis uses autonomic computing and knowledge management to govern cloud computing infrastructures. We find and structure possible reactive and proactive actions that prevent SLA violations, increase resource utilization and lower energy usage. First, we focus on VM resource (re-)configuration and investigate several knowledge management (KM) techniques such as case based reasoning, default logic, situation calculus, or a rule-based approach. We design and implement a KM-technique agnostic simulation engine to evaluate the suitability of these
Excess dose-related parameters (Vex, Rex, and iRex): novel predictors and late toxicity correlations in cervical cancer image-guided adaptive brachytherapy

Purpose In this paper, excess dose is originally proposed to represent the dose outside the target volume that encompass only organs at risk (OARs), not the whole dose volume of isodose surface volume (ISV). By means of spatial consideration, excess dose-related parameters would also compensate inconsistent applicator positions and OARs motion, which may deviate the identical dose small-volume assumption of D2cc. Late toxicity correlations of these parameters were investigated. Material and methods A retrospective review was performed on cervical cancer high-dose-rate image-guided adaptive brachytherapy (HDR-IGABT). From ISVs of 60 to 100 Gy EQD2 (a/β = 3), excess dose-related parameters were derived as following: toxicity negligible volume (Vneg = V60 of toxicity negligible organs; high-risk clinical target volume – HR-CTV, uterus, and vagina), excess dose volume (Vex = ISV – Vneg), Vneg normalized parameters of excess dose volume ratio (Rex = Vex/Vneg), and indirect excess dose volume ratio (iRex = ISV/Vneg). Relationships between toxicity and these parameters were analyzed using a mean difference and a probit analysis method. Net reclassification indices (NRIs) were used to compare iRex60 and D2cc gastrointestinal (GI) toxicity prediction. Results From 143 cases with an incidence of 34.9% and 10.5% of 3-year grade 2-4 GI and genitourinary (GU) toxicity, respectively, comparisons of means showed significant difference between grade 0-1 and 2-4 toxicities for late GI toxicity for all parameters, except ISV. There was a dose-response relationship with toxicity for each parameter across the range of 60-100 Gy EQD2. ED10 of iRex60 and iRex70 were 2.1 and 1.2, respectively. By comparing iRex60 and D2cc, additive and absolute NRIs were +6.45 and +7.69%, respectively. The reclassification significantly occurred in range of 65-75 Gy of rectum D2cc. Conclusions Excess dose-related parameters, including Vex, Rex, and iRex, showed significant mean differences and parameter-toxicity relationships for late GI but not for GU toxicities. Positive NRIs suggest iRex60 utilization for spatial control of dose expansion, in addition to high-dose control with OAR small volumes. Further investigations are needed to define the optimum use of these predictors.
Effect of Platelet-Rich Plasma on Intervertebral Disc Degeneration In Vivo and In Vitro: A Critical Review

Intervertebral disc degeneration (IDD) is a globally occurring disease that represents a significant cause of socioeconomic problems. Currently, the main method for treating IDD is surgery, including discectomy and vertebral fusion. Several in vitro experiments demonstrated that platelet-rich plasma (PRP) could stimulate cell proliferation and extracellular matrix regeneration. Additionally, in vivo experiments have proven that PRP injection could restore intervertebral disc height. Clinical studies demonstrated that PRP injection could significantly relieve patient pain. However, further studies are still required to clarify the roles of PRP in IDD prevention and treatment. This review is aimed at summarizing and critically analyzing the current evidence regarding IDD treatment with PRP.
Skin inflammatory response and efficacy of anti-epidermal growth factor receptor therapy in metastatic colorectal cancer (CUTACETUX)

ABSTRACT Anti-epidermal growth factor receptor (EGFR) monoclonal antibody is a standard treatment of metastatic colorectal cancer (mCRC) and its most common adverse effect is a papulopustular acneiform rash. The aim of the CUTACETUX study was to characterize the skin inflammatory response associated with this rash and its relation to treatment efficacy. This prospective study included patients with mCRC treated with first-line chemotherapy plus cetuximab. Patients underwent skin biopsies before the initiation of cetuximab (D0) and before the third infusion (D28), one in a rash zone and one in an unaffected zone. Expression of Th17-related cytokines (IL-17A, IL-21, IL-22), antimicrobial peptides (S100A7 and BD-2), innate response-related cytokines (IL-1β, IL-6, TNF-α and OSM), T-reg-related cytokines (IL-10 and TGF-β), Th1-related cytokine (IFN-γ), Th2-related cytokine (IL-4), Thymic stromal lymphopoietin and keratinocyte-derived cytokines (IL-8, IL-23 and CCL20) were determined by RT-PCR. Twenty-seven patients were included. Levels of most of the cytokines increased at D28 in the rash zone compared to D0. No significant association was observed between variations of cytokines levels and treatment response in the rash zone and only the increase of IL-4 (p = .04) and IL-23 (p = .02) levels between D0 and D28 in the unaffected zone was significantly associated with treatment response. Increased levels of IL-8 (p = .02), BD-2 (p = .02), IL-1β (p = .004) and OSM (p = .02) in the rash zone were associated with longer progression-free survival. Expression of Th2-related and keratinocyte-derived cytokines in the skin was associated with anti-EGFR efficacy. If this inflammatory signature can explain the rash, the exact mechanism by which these cytokines are involved in anti-EGFR tumor response remains to be studied.
A Combined Effect of Expression Levels of Obesity-Related Genes and Clinical Factors on Cancer Survival Rate

Obesity is directly associated with the risk of cancer in different organs, including breast, colon, and kidney. However, adipocytes could be utilized to control progression for some types of cancer, such as leukemia and breast cancer. To explore the potential correlation between adipocytes and cancer, the combined effect of expression levels of obesity-related genes and clinical factors (i.e., gender, race, menopausal status, history of smoking, tumor grade, body mass index (BMI), and history of drinking) on cancer survival rate was systemically studied. The expression levels of obesity-related genes in cancer tissues and normal tissues were downloaded from The Cancer Genome Atlas (TCGA). Kaplan–Meier curves were plotted using R programming language. The log-rank test was applied to explore the correlation between different clinical subgroups. The overexpression of the nine obesity-related genes (MC4R, TMEM18, KCTD15, GNPDA2, SH2B1, MTCH2, FTO, PCSK1, and GPR120) may associate with tumor-promoting factors in some organs (head and neck, gastrointestinal tract, liver, and gallbladder). Underexpressed LEPR, NEGR1, TMEM18, and SH2B1 genes prevented the progression and metastasis of kidney cancer. The combined effect of clinical factors and the expression levels of obesity-related genes on patients' survival was found to be significant. Our outcomes suggested that the alternations of DNA methylation patterns could result in the changes of expression levels of obesity-related genes, playing a critical role in tumor progression. The results of the current study may be utilized to supplement precision and personalized medicine, as well as provide novel insights for the development of treatment approaches for cancer.
Mental Health Problems in Chinese Healthcare Workers Exposed to Workplace Violence During the COVID-19 Outbreak: A Cross-Sectional Study Using Propensity Score Matching Analysis

Objective This study aimed at examining the effect of medical workplace violence (MWV) on the mental health of Chinese healthcare workers during the outbreak of coronavirus disease 2019 (COVID-19). Methods An anonymous online survey was issued to Chinese healthcare workers (N=1063) from 31 provinces and autonomous regions between February 13th and February 20th. Mental health was measured by the Chinese Depression Anxiety Stress Scales-21 (DASS-21). Medical workplace violence was measured using a single item, whether any type of workplace violence was experienced during the COVID-19 outbreak. Propensity score matching was used to assess the impact of MWV on mental health. Results Out of 1063, 217 (20.4%) reported experiencing MWV during the COVID-19 outbreak. Before matching, MWV was correlated with elevated mental health problems (b=8.248, p<0.001), after adjusting for other variables. After matching, Chinese healthcare workers who experienced MWV were more likely to suffer from mental health problems than those who did not. Conclusion MWV exerts a detrimental effect on mental health among Chinese healthcare workers during the COVID-19 outbreak. It is necessary to create a more supportive and safer work environment for healthcare workers at this special context of the COVID-19 outbreak.
Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and Trace Metals in Ejamah-Ebubu Oil Spill Site

The distribution of polyaromatic hydrocarbons (PAHs) at different georeferenced sampling points: Nwata A, Nwata B, Nwata 3’, Ochani and Eyeyaro in one of the most contaminated mangrove swamp in Nigeria, Ejamah-Ebubu oil spill site was studied. The physico-chemical analysis of the sediment samples and trace metals were also conducted. PAHs were analyzed using gas-chroma-tography flame ionization detection while metals with atomic absorption spectrophotometry (AAS). The result showed that the total PAHs (summation of 16 US EPA priority PAHs) were present at all sampling points and the concentration ranged from 0.070 to 5.521 ppm with Nwatu A > Nwatu B > Ochani > Egeyaro > Nwatu 3’. The pH of the site is acidic. The concentration of trace metals for most sampling points is iron > chromium > lead > nickel > vanadium. Our result indicates that the concentration of PAHs is at level higher than the permitted level therefore; it is recommended that Ejamah-Ebubu oil spill site be remediated.
Response of Odontoblast to the Bio-Calcium Phosphate Cement

Purpose: If the tooth structure is damaged, then it is impossible to regenerate the tooth. The materials used to restore the tooth structure are not related to the composition of the tooth. The materials used to restore the structure can't replace the natural tooth because they just fill the defective structure. Calcium phosphate cement remineralizes the dentin and almost replaces the natural tooth, but there are some disadvantages. We conducted basic tests with Biomimetic CPC (Bio-CPC) to make sure of the possibility of the biomaterial to remineralize the defective tooth structure. Methods: In this study, the bioactivity and biocompatibility of Bio-CPC were evaluated for its potential value as the bio-material for regeneration of damaged tooth structure by conducting a cell toxicity assay (WST-1 assay), a cytokinesis-block micronucleus assay, a chromosomal aberration test, total RNA extraction and RT-PCR on MDPC-23 mouse odontoblast-like cells. Results: The in vitro cytotoxicity test showed that the Bio-CPC was fairly cytocompatible for the MDPC-23 mouse odontoblast-like cells. Conclusion: Bio-CPC has a possibility to be a new biomaterial and further study of Bio-CPC is needed.