Miracle-dz/UniFAR-FTUs huggingface dataset:
An Analysis of the Impact of Valve Closure Time on the Course of Water Hammer

Abstract The knowledge of transient flow in pressure pipelines is very important for the designing and describing of pressure networks. The water hammer is the most common example of transient flow in pressure pipelines. During this phenomenon, the transformation of kinetic energy into pressure energy causes significant changes in pressure, which can lead to serious problems in the management of pressure networks. The phenomenon is very complex, and a large number of different factors influence its course. In the case of a water hammer caused by valve closing, the characteristic of gate closure is one of the most important factors. However, this factor is rarely investigated. In this paper, the results of physical experiments with water hammer in steel and PE pipelines are described and analyzed. For each water hammer, characteristics of pressure change and valve closing were recorded. The measurements were compared with the results of calculations perfomed by common methods used by engineers - Michaud’s equation and Wood and Jones’s method. The comparison revealed very significant differences between the results of calculations and the results of experiments. In addition, it was shown that, the characteristic of butterfly valve closure has a significant influence on water hammer, which should be taken into account in analyzing this phenomenon. Comparison of the results of experiments with the results of calculations? may lead to new, improved calculation methods and to new methods to describe transient flow.
Characterization of Atmospheric Organic and Elemental Carbon of PM2.5 in a Typical Semi-Arid Area of Northeastern China

ABSTRACTIn the spring of 2006, daily particulate matter (PM2.5) aerosol samples were collected in Tongyu, a semi-arid area in northeastern China. The concentrations of organic carbon (OC) and elemental carbon (EC) were determined with a thermal/optical carbon analyzer in the filter samples. The average concentrations of OC and EC in PM2.5 were 14.1 ± 8.7 and 2.0 ± 1.3 μg/m3, respectively. A good correlation between OC and EC was observed during the spring season, suggesting that they might be derived from similar sources. The correlation between OC and K+ was high (R = 0.74), and the K+/OC ratio, as determined from their linear regression slope, reached 2.57. The good correlation and high K+/OC ratio indicated that biomass-burning was probably one of the major sources of OC in this region. The concentrations of estimated secondary organic carbon (SOC) in PM2.5 in Tongyu ranged from below the detection limit to 26.1 μg/m3 (mean, 5.9 μg/m3). The percentages of SOC in OC and in PM2.5 mass were 42.0% and 2.1%, respectively. The SOC concentrations during dust storm (DS) periods were higher than those during non-dust storm (NDS) ones, suggesting that chemical reaction processes involving gas-particle conversion occurred during the long-distance transport of aerosol particles.
Azumaya Algebras and Canonical Components

Let $M$ be a compact 3-manifold and $\Gamma=\pi_1(M)$. Work of Thurston and Culler--Shalen established the $\mathrm{SL}_2(\mathbb{C})$ character variety $X(\Gamma)$ as fundamental tool in the study of the geometry and topology of $M$. This is particularly the case when $M$ is the exterior of a hyperbolic knot $K$ in $S^3$. The main goals of this paper are to bring to bear tools from algebraic and arithmetic geometry to understand algebraic and number theoretic properties of the so-called canonical component of $X(\Gamma)$, as well as distinguished points on the canonical component, when $\Gamma$ is a knot group. In particular, we study how the theory of quaternion Azumaya algebras can be used to obtain algebraic and arithmetic information about Dehn surgeries, and perhaps of most interest, to construct new knot invariants that lie in the Brauer groups of curves over number fields.
Metabolism of sesamin by CYPs and UGTs in human liver

Sesamin is a major lignan in sesame, and its biological effects such as antioxidant effect, anti-carcinogenic effects, and suppression of hypertension have been extensively studied by many researchers. However, its metabolic pathways and metabolic enzymes in human bodies have not been identified. Recently we demonstrated that CYP2C9 was the most important cytochrome P450 isoform in human liver. Next, we focused on metabolism of sesamin mono-catechol by cytochrome P450 or UDP-glucuronosyltransferase (UGT). Further catecholization of sesamin mono-catechol by cytochrome P450 enhances its anti-oxidant activity, whereas glucuronidation by UGT strongly reduces anti-oxidant activity. In human liver microsomes, glucuronidation activity toward sesamin mono-catechol was much higher than the di-catecholization activity. In contrast, both activities were similar in rat liver microsomes. These results suggest a large species-based difference between humans and rats in sesamin metabolism. In vitro studies using 10 individual human liver microsomes suggested that UGT2B7 was responsible for glucuronidation of sesamin mono-catechol in human liver. In addition, we observed a significant methylation activity toward sesamin mono-catechol by catechol O-methyl transferase (COMT) in human liver cytosol. Based on these results, we concluded that CYP2C9, UGT2B7, and COMT played essential roles in the metabolism of sesamin in human liver.
Effect of parameter choice in root water uptake models – the arrangement of root hydraulic properties within the root architecture affects dynamics and efficiency of root water uptake

Abstract. Detailed three-dimensional models of root water uptake have become increasingly popular for investigating the process of root water uptake. However, they suffer from a lack of information on important parameters, particularly on the spatial distribution of root axial and radial conductivities, which vary greatly along a root system. In this paper we explore how the arrangement of those root hydraulic properties and branching within the root system affects modelled uptake dynamics, xylem water potential and the efficiency of root water uptake. We first apply a simple model to illustrate the mechanisms at the scale of single roots. By using two efficiency indices based on (i) the collar xylem potential ("effort") and (ii) the integral amount of unstressed root water uptake ("water yield"), we show that an optimal root length emerges, depending on the ratio between roots axial and radial conductivity. Young roots with high capacity for radial uptake are only efficient when they are short. Branching, in combination with mature transport roots, enables soil exploration and substantially increases active young root length at low collar potentials. Second, we investigate how this shapes uptake dynamics at the plant scale using a comprehensive three-dimensional root water uptake model. Plant-scale dynamics, such as the average uptake depth of entire root systems, were only minimally influenced by the hydraulic parameterization. However, other factors such as hydraulic redistribution, collar potential, internal redistribution patterns and instantaneous uptake depth depended strongly on the arrangement on the arrangement of root hydraulic properties. Root systems were most efficient when assembled of different root types, allowing for separation of root function in uptake (numerous short apical young roots) and transport (longer mature roots). Modelling results became similar when this heterogeneity was accounted for to some degree (i.e. if the root systems contained between 40 and 80% of young uptake roots). The average collar potential was cut to half and unstressed transpiration increased by up to 25% in composed root systems, compared to homogenous ones. Also, the least efficient root system (homogenous young root system) was characterized by excessive bleeding (hydraulic lift), which seemed to be an artifact of the parameterization. We conclude that heterogeneity of root hydraulic properties is a critical component for efficient root systems that needs to be accounted for in complex three-dimensional root water uptake models.
Integrating the invisible fabric of nature into fisheries management

Overfishing and environmental change have triggered many severe and unexpected consequences. As existing communities have collapsed, new ones have become established, fundamentally transforming ecosystems to those that are often less productive for fisheries, more prone to cycles of booms and busts, and thus less manageable. We contend that the failure of fisheries science and management to anticipate these transformations results from a lack of appreciation for the nature, strength, complexity, and outcome of species interactions. Ecologists have come to understand that networks of interacting species exhibit nonlinear dynamics and feedback loops that can produce sudden and unexpected shifts. We argue that fisheries science and management must follow this lead by developing a sharper focus on species interactions and how disrupting these interactions can push ecosystems in which fisheries are embedded past their tipping points.
Knowledge of Fathers’ Support during Labor: From Arabic Fathers’ Perspective

Aim: The aim of this study was to assess the kind of labor support Arab fathers could offer their wives. Design and Method: An interpretative phenomenological approach was used to reveal the meaning attributed by Arabic fathers regarding their support during labor. Individual, semi-structured interviews were conducted with 19 Arabic fathers. The analysis was done by using Smith’s model of interpretive phenomenological analysis (IPA) together with software package NVivo7. Findings: The analysis of the interviews illustrated the types of labor support offered by Arabic fathers to their wives. Three main themes emerged from the data: physical support, emotional support, and spiritual support. Conclusion: The support offered by Arabic fathers was in the minimal degree and missing practical support. Socio cultural issues and health policies prevented fathers from playing an active role during labor. There is a need to develop policies and regulations that enhance more inclusion of fathers in maternity services including the labor room.
Latent Space Oddity: on the Curvature of Deep Generative Models

Deep generative models provide a systematic way to learn nonlinear data distributions, through a set of latent variables and a nonlinear "generator" function that maps latent points into the input space. The nonlinearity of the generator imply that the latent space gives a distorted view of the input space. Under mild conditions, we show that this distortion can be characterized by a stochastic Riemannian metric, and demonstrate that distances and interpolants are significantly improved under this metric. This in turn improves probability distributions, sampling algorithms and clustering in the latent space. Our geometric analysis further reveals that current generators provide poor variance estimates and we propose a new generator architecture with vastly improved variance estimates. Results are demonstrated on convolutional and fully connected variational autoencoders, but the formalism easily generalize to other deep generative models.
Development of phase shift lithography for the production of metal-oxide-metal diodes

Metal-oxide-metal (MOM) diodes have been produced by combining two novel techniques: a reactive ion etche and subsequent plasma oxidation, and a phase shift lithography process. This has resulted in a significant reduction in device feature sizes, down to sub-micron dimensions and with an improved zero voltage curvature coefficient of up to 2.8 V-1 for the associated diodes. Given the use of MOM diodes in high speed rectification applications, the combination of the reduction in diode area as well as the controlled oxide growth aims to assist in the improved cutoff frequency of the devices, thus ensuring the potential for high speed applications.
The Cryosphere Transient thermal effects in Alpine permafrost

In high mountain areas, permafrost is important because it influences the occurrence of natural hazards, because it has to be considered in construction practices, and because it is sensitive to climate change. The assessment of its distribution and evolution is challenging because of highly variable conditions at and below the surface, steep topography and varying climatic conditions. This paper presents a systematic investigation of effects of topography and climate variability that are important for subsurface temperatures in Alpine bedrock permafrost. We studied the effects of both, past and projected future ground surface temperature variations on the basis of numerical experimentation with simplified mountain topography in order to demonstrate the principal effects. The modeling approach applied combines a distributed surface energy balance model and a three-dimensional subsurface heat conduction scheme. Results show that the past climate variations that essentially influence present-day permafrost temperatures at depth of the idealized mountains are the last glacial period and the major fluctuations in the past millennium. Transient effects from projected future warming, however, are likely larger than those from past climate conditions because larger temperature changes at the surface occur in shorter time periods. We further demonstrate the accelerating influence of multi-lateral warming in steep and complex topography for a temperature signal entering the subsurface as compared to the situation in flat areas. The effects of varying and uncertain material properties (i.e., thermal properties, porosity, and freezing characteristics) on the subsurface temperature field were examined in sensitivity studies. A considerable influence of latent heat due to water in low-porosity bedrock was only shown for simulations over time periods of decades to centuries. At the end, the model was applied to the toCorrespondence to: J. Noetzli (jeannette.noetzli@geo.uzh.ch) pographic setting of the Matterhorn (Switzerland). Results from idealized geometries are compared to this first example of real topography, and possibilities as well as limitations of the model application are discussed.
A cross-national study of work engagement as a mediator between job resources and proactive behaviour

This study investigates the mediating role of work engagement (i.e. vigour and dedication) among job resources (i.e. job control, feedback and variety) and proactive behaviour at work. This mediating role was investigated, using Structural Equation Modelling in two independent samples from Spain (n = 386 technology employees) and the Netherlands (n = 338 telecom managers). Results in both samples confirmed that work engagement fully mediates the impact of job resources on proactive behaviour. Subsequent multigroup analyses revealed that the strengths of the structural paths of the mediation model were invariant across both national samples, underscoring the cross-national validity of the model
Photochemical oxygen consumption in marine waters: A major sink for colored dissolved organic matter?

Quantification of photochemical O2 uptake provides a measure of total chemical photooxidation of dissolved organic matter (DOM). Here we study this process and present estimates suggesting that photooxidation has the potential to significantly modify marine DOM pools, complementing or exceeding oxidation via coupled chemical‐biological pathways. We measured apparent quantum yields (AQYs) of photobleaching, O2 uptake, and H2O2 production in several coastal marine samples and in dilutions of a tropical estuarine water with oligotrophic seawater. O2‐loss AQYs varied little among samples or with dilution but decreased linearly from 1.2×10–3 at 300 nm to 0.3×10–3 at 400 nm and dropped about threefold to near‐constant values with increasing absorbed light dose. H2O2 production, about 45% of O2 uptake, showed similar dependencies, whereas singlet oxygen (O2 (1Δg)) reactions contributed less than 1% of O2 uptake for typical coastal water. Implications of these findings for photochemical O2, H2O2, and DOM cycling are discussed.
Unevenness Point Descriptor for Terrain Analysis in Mobile Robot Applications

In recent years, the use of imaging sensors that produce a three-dimensional representation of the environment has become an efficient solution to increase the degree of perception of autonomous mobile robots. Accurate and dense 3D point clouds can be generated from traditional stereo systems and laser scanners or from the new generation of RGB-D cameras, representing a versatile, reliable and cost-effective solution that is rapidly gaining interest within the robotics community. For autonomous mobile robots, it is critical to assess the traversability of the surrounding environment, especially when driving across natural terrain. In this paper, a novel approach to detect traversable and non-traversable regions of the environment from a depth image is presented that could enhance mobility and safety through integration with localization, control and planning methods. The proposed algorithm is based on the analysis of the normal vector of a surface obtained through Principal Component Analysis and it leads to the definition of a novel, so defined, Unevenness Point Descriptor. Experimental results, obtained with vehicles operating in indoor and outdoor environments, are presented to validate this approach.
Sweetness and Food Preference

Human desire for sweet taste spans all ages, races, and cultures. Throughout evolution, sweetness has had a role in human nutrition, helping to orient feeding behavior toward foods providing both energy and essential nutrients. Infants and young children in particular basemany of their food choices on familiarity and sweet taste. The low cost and ready availability of energycontaining sweeteners in the food supply has led to concerns that the rising consumption of added sugars is the driving force behind the obesity epidemic. Low-calorie sweeteners are one option for maintaining sweet taste while reducing the energy content of children’s diets. However, their use has led to further concerns that dissociating sweetness from energy may disrupt the balance between taste response, appetite, and consumption patterns, especially during development. Further studies, preferably based on longitudinal cohorts, are needed to clarify the developmental trajectory of taste responses to low-calorie sweeteners and their potential impact on the diet quality of children and youth. J. Nutr. doi: 10.3945/jn.111. 149575.
Nitric oxide – mediated signalization and nitrosative stress in neuropathology / Azot oksid – posredovana signalizacija i nitrozativni stres u neuropatologiji

Summary Nitric oxide (NO) is an important signalling molecule in a variety of physiological processes. NO, a gas, is produced from L-arginine by different isoforms of the nitric oxide synthase and serves as mediator in important physiological functions, such as promoting vasodilation of blood vessels and mediating communication between nervous system cells. Contradictory to its physiologic actions, free radical activity of NO can cause cellular damage by the induction of nitrosative stress with significant implications on nervous system diseases. Although the mechanism of NOmediated neurodegeneration still remains unclear, numerous studies suggest its crucial role in modification of protein functions by nitrosylation and nitro-tyrosination. NO contributes to glutamate excitotoxicity, participates in organelle fragmentation, inhibits mitochondrial respiratory complexes and mobilizes zinc from the internal stores. Recently, NO has been emerged as a mediator of epigenetic gene expression and chromatin changes. Besides, NO is a key mediator in the regulation of inflammatory and immune response of the central nervous system. It is involved in down regulation of several aspects of CNS inflammation, but also has a dual role in that it is required for inflammation in some situations. Kratak sadržaj Azot monoksid je va`an signalni molekul u brojnim fiziolo{kim procesima. Ovaj gas se stvara iz L-argi - nina dejstvom tri izoforme azot monoksid sintaze i medijator je va`nih fiziolo{kih funkcija, kao {to su posredovanje u re - gulaciji tonusa krvnih sudova i komunikaciji }elija nervnog sistema. Nasuprot ovim ulogama, kao slobodni radikal, NO mo`e izazvati }elijsko o{te}enje indukcijom nitrozativnog stresa, {to ima zna~ajne implikacije u bolestima nervnog sistema. Mada je mehanizam neurodegeneracije posredovane azot monoksidom jo{ uvek nerazja{njen, brojne studije uka - zu ju na njegovu klju~nu ulogu u modifikaciji funkcije protei - na kroz procese S-nitrozilacije i nitrovanja tirozina. On doprinosi glutamatnoj ekscitotoksi~nosti, u~estvuje u fragmentaciji organela, inhibi{e mitohondrijalne respiratorne komplekse i mobili{e cink iz unutra{njih depoa. Nedavno je ukazano da mo`e biti medijator epigenetske genske ekspresije i promena hromatina. Pored toga, NO je klju~ni posrednik u regulaciji inflamatornog i imunog odgovora CNS. On u~estvuje u nishodnoj regulaciji nekoliko aspekata inflamacije CNS, ali tako|e ispoljava dualisti~ke efekte u uslovima inflamacije.
Variability of heat and salinity content in the North Atlantic in the last decade

Abstract. The analysis of the heat and salinity contents has been made for the Northern Atlantic for the decade between January 1999 and December 2008. This analysis is based on the Argo profiling data for the upper 2000 m. Basin-averaged values of heat content deviation (HCD) and salinity content deviation (SCD) are robust and stable. The HCD and SCD demonstrate positive trends in the last decade in the upper 2000 m of the North Atlantic. The linear trend of HCD and SCD are (11.14±3.17)×1020 J/yr, and (2.80±1.17)×1013 kg/yr, respectively. Both trends are significant at 95% level of significance.
Usability, aesthetics and emotions in human–technology interaction

In the past, research on human–technology interaction has almost exclusively concentrated on aspects of usefulness and usability. Despite the success of this line of research, its narrow perspective has recently become a target for criticism. To explain why people prefer some systems over others, factors such as aesthetic qualities and emotional experiences play an important role in addition to instrumental aspects. In the following, we report three experiments that illustrate the importance of such factors. In the first experiment, we study the role of emotions in human–technology interaction by using Scherer's (1984) component theory of emotions as a theoretical foundation. A combination of methods is derived from that theory and employed to measure subjective feelings, motor expressions, physiological reactions, cognitive appraisals, and behaviour. The results demonstrate that the manipulation of selected system properties may lead to differences in usability that affect emotional user reactions. The s.
Polarization-mode hopping in single-mode vertical-cavity surface-emitting lasers: Theory and experiment

In this paper, we present a theoretical and experimental analysis of stochastic effects observed in polarization switching vertical-cavity surface-emitting lasers. We make a thorough comparison between theoretical predictions and experiments, comparing measured quasipotentials and dwell times. The correspondence between our theoretical model based on stochastic intensity rate equations and the experiments is found to be very good.