Miracle-dz/UniFAR-FTUs huggingface dataset:
Investigation of the Impact of Orthogonal Cutting Processes on Nanocrystalline Surface Layer Generation

The present work analyzes the influence of an orthogonal machining process on the generation of nanocrystalline surface layers. Thereby, AISI 4140 is used as work piece material. Metallic parts with a severe nanocrystalline grain refinement in the near-surface area show many beneficial properties. Such surface layers considerably influence the friction and wear characteristics of the work piece in a subsequent usage as design elements working under tribological loads. The focus of this paper is an experimental analysis of a finishing orthogonal cutting operation, carried out with a broaching machine, to generate nanocrystalline surface layers. The influence of process and geometry parameters on the generation of nanocrystalline surfaces is investigated with the aim to massively decrease the grain size in the work piece surface layer. Parameters that are studied and taken into account in the manufacturing process are cutting edge radius rβ, depth of cut h and cutting velocity vc. The cutting edge radius rβ is modified by a drag finishing process. The generation of nanocrystalline surface layers is especially influenced by the design of the uncoated carbide cutting tools. Additionally, cutting force Fc and passive force Fp are determined by a 3-component dynamometer to calculate the relationship between specific cutting force kc and specific passive force kp. The temperature beneath the clearance face is detected by a fiber optic pyrometer. These measurement methods and devices are applied to detect the impact of the most relevant measurement values occurring during machining and causing a drastic reduction of grain size in the surface layer. The evaluation of the manufacturing process is carried out by detailed analyses of the microstructural conditions in the surface layer after processing using a Focused Ion Beam (FIB) system. These material characterizations provide information about the surface engineering concerning the microstructural changes in the surface layer of the work piece due to finishing orthogonal cutting processes.
Determinants of business cycles in small scale macroeconomic models: the German case

We identify measures of shocks to total factor productivity and preferences from two real business cycle models and subject them to Granger causality tests to see whether they can be considered exogenous to other plausible sources of the German business cycle. For West German data from 1960.i to 1989.iv we conclude that our measures of shocks are indeed exogenous. This contrasts with similar studies for other countries that question the exogeneity of either productivity or preference shocks. For the period 70.i to 01.iv we find that M3 Granger causes all of our shock measures. We attribute this to the breaks in our time series associated with the German reunification in 1990 and the European Monetary Union in 1999.
Improved pure SH SAW transduction efficiency on LGS using finite thickness gratings

Pure shear horizontal surface acoustic wave (SH SAW) orientations exist on trigonal class 32 crystals along (0°, θ, 90°). In particular, this mode has been recently considered on single crystal langasite (LGS) for liquid and biological sensor applications due to reduced propagation loss in the presence of liquid-loaded surface. A limitation of the pure SH SAW orientations for device applications has been the significant excitation of the shear horizontal bulk acoustic wave (SH BAW) by the interdigital transducer (IDT), which compromises the SH SAW transduction efficiency and thus increases SH SAW device loss. Previous work by the authors verified that an infinitesimally thin metallic guiding layer used in the propagation path around the IDT typically increases the SH SAW transduction efficiency ηSHSAW , defined as the ratio of SH SAW power to total IDT input power, from less than 1% (no layer) to 60% (infinitesimally thin metallic layer) on LGS, Euler angles (0°, 22°, 90°) for a 240 split finger electrode IDT. In this work, finite thickness periodic grating guiding structures are explored along LGS (0°, 22°, 90°) to further improve the IDT ηSHSAW. The structure studied consists of a finite number of IDT electrodes bordered by gratings on both sides. The model implemented uses orthogonal Chebyshev polynomial basis functions in conjunction with the finite element method and harmonic admittance (HA) technique to study the SH SAW mode excitation efficiency in the referred structure. The IDT ηSHSAW is examined as a function of: electrode material and normalized thickness (h/λ) where h is electrode thickness and λ is the wavelength; metallization ratio (a/p) where a and p are electrode width and center-to-center spacing, respectively; and number of split IDT finger electrodes. The analysis performed shows a significant difference in ηSHSAW if high density electrode gratings, such as gold (Au) or platinum (Pt) are used instead of low-density gratings, such as aluminum (Al). For instance, using 282 split finger electrode IDT and surrounding gratings composed of Au or Pt electrodes, with h/λ = 1%, results in ηSHSAW = 99%. If Al is used, a reduced ηSHSAW = 54% is achieved for the same h/λ = 1%. Moreover, to achieve ηSHSAW = 99% with Al electrodes, the required value of h/λ is about 8.5%, a nearly ten-fold increase in metallization thickness over Au or Pt electrodes. The effects of metallization ratio a/p on ηSHSAW have also been studied and indicate that higher metallization ratios lead to higher ηSHSAW. Numerical and experimental IDT admittance is compared, validating the analysis performed. The work reported shows that finite thickness gratings can significantly improve the SH SAW IDT performance, reducing the amount of SHBAW excited by the IDT, and thus leading to high efficiency LGS SH SAW devices for biosensor applications.
Rapid prototyping of micro-optics on organic light emitting diodes and organic photo cells by means of two-photon 3D lithography and nano-imprint lithography

Provided that suitable materials are available, novel structuring methods, such as two-photon-3D-lithography (2P3DL) and nano-imprint-lithography (NIL) are promising approaches for the fabrication of organic complex 2D and 3D structures. Optical materials based on photopolymerizable resins combined with novel efficient multi-photon photoinitiators can be used for a fast and simple fabrication of μ-optical components for MOEMS. The true 3D capabilities and the high spatial resolution of the 2P3DL permit the fabrication of nearly any optical designs from CAD. With supplementary feedback controlled positioning of the laser focus, a material can be processed at an explicit target position, e.g. on an organic LED or photo cell. The position of fabricated μ-optics relative to such devices is determined by 3D sample registration prior to the structuring process. Therefore, the alignment of laser written structures to existing sample features becomes a part of the fabrication process and no further assembly is required. We demonstrate the design and the fabrication of various μ-optical structures such as waveguides and μ-lenses for photonic μ-systems by means of 2P3DL. Furthermore, μ-lens masters prototyped by means of two-photon-3D-lithography and their replication via a PDMS stamp by means of NIL are presented. In addition, it can be shown that such μ-optical systems can be fabricated in situ on organic LEDs or organic photo cells enabling powerful building blocks for μ-optical systems.
Host cell DNA chain initiation protein requirements for replication of bacteriophage G4 replicative-form DNA

Bacteriophages G4ev1 and G4bs1 are simple temperature-resistant derivatives of wild-type G4 as demonstrated by restriction endonuclease analyses. The rate of replication of the duplex replicative-form DNA of these phages was normal in dnaB and dnaC mutants of the host, whereas the rate was markedly reduced in a dnaG host mutant at the restrictive temperature. We conclude that G4 duplex DNA replication requires the host cell dnaG protein, but not the dnaB and dnaC proteins. The reasons for the differences between our conclusions and those based on previously published data are documented and discussed.
Homocysteine metabolism.

Homocysteine is a sulfur amino acid whose metabolism stands at the intersection of two pathways: remethylation to methionine, which requires folate and vitamin B12 (or betaine in an alternative reaction); and transsulfuration to cystathionine, which requires pyridoxal-5'-phosphate. The two pathways are coordinated by S-adenosylmethionine, which acts as an allosteric inhibitor of the methylenetetrahydrofolate reductase reaction and as an activator of cystathionine beta-synthase. Hyperhomocysteinemia, a condition that recent epidemiological studies have shown to be associated with increased risk of vascular disease, arises from disrupted homocysteine metabolism. Severe hyperhomocysteinemia is due to rare genetic defects resulting in deficiencies in cystathionine beta synthase, methylenetetrahydrofolate reductase, or in enzymes involved in methyl-B12 synthesis and homocysteine methylation. Mild hyperhomocysteinemia seen in fasting conditions is due to mild impairment in the methylation pathway (i.e. folate or B12 deficiencies or methylenetetrahydrofolate reductase thermolability). Post-methionine-load hyperhomocysteinemia may be due to heterozygous cystathionine beta-synthase defect or B6 deficiency. Early studies with nonphysiological high homocysteine levels showed a variety of deleterious effects on endothelial or smooth muscle cells in culture. More recent studies with human beings and animals with mild hyperhomocysteinemia provided encouraging results in the attempt to understand the mechanism that underlies this relationship between mild elevations of plasma homocysteine and vascular disease. The studies with animal models indicated the possibility that the effect of elevated homocysteine is multifactorial, affecting both the vascular wall structure and the blood coagulation system.
Cooperative cortical network for categorical processing of Chinese lexical tone

Significance The variation of pitch in speech not only creates the intonation for affective communication but also signals different meaning of a word in tonal languages, like Chinese. Due to its subtle and brisk pitch contour distinction between tone categories, the underlying neural processing mechanism is largely unknown. Using direct recordings of the human brain, we found categorical neural responses to lexical tones over a distributed cooperative network that included not only the auditory areas in the temporal cortex but also motor areas in the frontal cortex. Strong causal links from the temporal cortex to the motor cortex were discovered, which provides new evidence of top-down influence and sensory–motor interaction during speech perception. In tonal languages such as Chinese, lexical tone with varying pitch contours serves as a key feature to provide contrast in word meaning. Similar to phoneme processing, behavioral studies have suggested that Chinese tone is categorically perceived. However, its underlying neural mechanism remains poorly understood. By conducting cortical surface recordings in surgical patients, we revealed a cooperative cortical network along with its dynamics responsible for this categorical perception. Based on an oddball paradigm, we found amplified neural dissimilarity between cross-category tone pairs, rather than between within-category tone pairs, over cortical sites covering both the ventral and dorsal streams of speech processing. The bilateral superior temporal gyrus (STG) and the middle temporal gyrus (MTG) exhibited increased response latencies and enlarged neural dissimilarity, suggesting a ventral hierarchy that gradually differentiates the acoustic features of lexical tones. In addition, the bilateral motor cortices were also found to be involved in categorical processing, interacting with both the STG and the MTG and exhibiting a response latency in between. Moreover, the motor cortex received enhanced Granger causal influence from the semantic hub, the anterior temporal lobe, in the right hemisphere. These unique data suggest that there exists a distributed cooperative cortical network supporting the categorical processing of lexical tone in tonal language speakers, not only encompassing a bilateral temporal hierarchy that is shared by categorical processing of phonemes but also involving intensive speech–motor interactions over the right hemisphere, which might be the unique machinery responsible for the reliable discrimination of tone identities.
Adaptive Packet Level Redundancy Mechanisms for Reliable Mobile Multicast: Proposed Architecture and Performance Analysis

In this paper, we investigate how packet level redundancy mechanisms could be combined with ARQ (Automatic Repeat reQuest) to achieve scalable reliable mobile multicast transmissions. We consider three redundancy mechanisms. The first one called FEC-based mechanism is that redundant packets are achieved by FEC (Forward Error Correction) encoding. The second type called Replicate-based mechanism is that redundant packets are achieved by replication. Combination of FEC- based and replicate-based is used in the last mechanism called FEC-Replicate-based mechanism. We also propose a novel adaptive packet level redundancy mechanism based on FEC-Replicate-based mechanism. To design a novel packet level redundancy mechanism, we start with analyzing comparative performance of four reliable multicast mechanisms, which are Pure NAK-based mechanism, NAK-FEC-based mechanism, NAK-Replicate- based mechanism, and NAK-FEC-Replicate-based mechanism. In addition, simulation is provided to evaluate the four mechanisms when both data packets and feed back packets might be lost. The simulation and analysis show that FEC-Replicate-based mechanism could be the best for using in reliable mobile multicast applications, which have different packet priorities.
MCExplorer: Interactive Exploration of Multiple (Subspace) Clustering Solutions

Large amounts of data are ubiquitous today. Data mining methods like clustering were introduced to gain knowledge from these data. Recently, detection of multiple clusterings has become an active research area, where several alternative clustering solutions are generated for a single dataset. Each of the obtained clustering solutions is valid, of importance, and provides a different interpretation of the data. The key for knowledge extraction, however, is to learn how the different solutions are related to each other. This can be achieved by a comparison and analysis of the obtained clustering solutions. We introduce our demo MCExplorer, the first tool that allows for interactive exploration, browsing, and visualization of multiple clustering solutions on several granularities. MCExplorer is applicable to the output of both fullspace and subspace clustering approaches.
BE-SONOS: A bandgap engineered SONOS with excellent performance and reliability

A bandgap engineered SONOS with greatly improved reliability properties is proposed. This concept is demonstrated by a multilayer structure of O1/N1/O2/N2/O3, where the ultra-thin "O1/N1/O2" serves as a non-trapping tunneling dielectric, N2 the high-trapping-rate charge storage layer, and O3 the blocking oxide. The ultra-thin "O1/N1/O2" provides a "modulated tunneling barrier" - it suppresses direct tunneling at low electric field during retention, while it allows efficient hole tunneling erase at high electric field due to the band offset. Therefore, this BE-SONOS offers fast hole tunneling erase, while it is immune to the retention problem of the conventional SONOS. With a N+-poly gate, we achieve self-convergent erased Vt ~3 V, suitable for NOR flash application. On the other hand, by using a P+-poly gate, a depletion mode device (Vt < 0) is obtained, and a very large memory window (> 6 V) is achieved, ideal for MLC-NAND application. Excellent performance and reliability for both applications are demonstrated. Furthermore, with this simple structure and no new materials BE-SONOS is readily manufacturable
Enhanced permittivity and multi-region microwave absorption of nanoneedle-like ZnO in the X-band at elevated temperature

We fabricated nanoneedle-like ZnO (ZnOn) by a facile combustion synthesis route, demonstrating the original observations on the complex permittivity of ZnOn ranging from 298 to 573 K and in the X band. Both real and imaginary permittivities (e′ and e′′) of ZnOn depend on temperature and frequency. The e′ increases while the e′′ possesses a maximum value with increasing temperature. The maximum value of e′′ appears at 473 K, and the corresponding loss tangent increases by 100% than that at 298 K. The relaxations in e′′ mainly arise from dipole polarization and interfacial polarization in ZnOn. Multi-region microwave absorption of ZnOn appears at the investigated temperature and frequency as well as thickness. The minimum reflection loss value reaches −44 dB, which is superior to the previous reports. These findings provide a novel and feasible strategy to tune microwave absorption towards a structural absorber at elevated temperature.
Quantifying Heteroskedasticity Using Slope of Local Variances Index

In econometrics, heteroskedasticity refers to the case when the variances of the error terms of the data in hand are not equal. Heteroskedastic time series are challenging to different forecasting models. However, all available solutions adopt the strategy of accommodating heteroskedasticity in the time series and consider it as a type of noise. Some statistical tests were developed over the past three decades to determine whether a time series features heteroskedastic behaviour. This paper presents a novel strategy to handle this problem by deriving a quantifying measure for heteroskedasticity. The proposed measure relies on the definition of heteroskedasticity as a time-variant variance in the time series. In this work, heteroskedasticity is measured by calculating local variances using linear filters, estimating variance trends, calculating changes in variance slopes, and finally obtaining the average slope angle. The results confirm that the proposed index complies with the widely popular heteroskedasticity tests.
Return to work after first myocardial infarction in 1991-1996 in Finland.

BACKGROUND A substantial number of myocardial infarctions (MI) occur at working age. It is, however, insufficiently well known how many of these patients return to work after their MI. METHODS Sources of information were the Hospital Discharge Register, the Causes of Death Register and the registers for social security benefits. Availability for the labour market was used as the return to work criterion. Altogether 10,244 persons (8,733 men, 1,511 women) aged 35-59 years had their first MI or coronary death during 1991-1994 in Finland. Persons who survived for 28 days and were not on pension at the time of MI were included in a two-year follow-up. RESULTS Twenty-nine per cent of patients were already pensioned at the time of their first MI. Of the patients not pensioned at the time of their MI, 4,929 were alive two years after the event. Of them, 38% of men and 40% of women received disability pension, 3% of both genders were on sick leave and 1% of both genders were on unemployment pension. The remainder, 58% of men and 56% of women, did not receive any of these benefits, thus, being available to the labour force. CONCLUSIONS Nearly one-third of persons having their first MI at working age were already out of the labour force at the time of their MI. Of those who were not pensioned and who survived the event, slightly more than half were available to the labour market two years later.
Optimal fractional repetition codes and fractional repetition batch codes

Fractional repetition (FR) codes is a family of codes for distributed storage systems (DSS) that allow uncoded exact repairs with minimum repair bandwidth. In this work, we consider a bound on the maximum amount of data that can be stored using an FR code. Optimal FR codes which attain this bound are presented. The constructions of these FR codes are based on families of regular graphs, such as Turán graphs and graphs with large girth; and on combinatorial designs, such as transversal designs and generalized polygons. In addition, based on a connection between FR codes and batch codes, we propose a new family of codes for DSS, called fractional repetition batch codes, which allow uncoded efficient exact repairs and load balancing which can be performed by several users in parallel.
Reference intervals: current status, recent developments and future considerations

Reliable and accurate reference intervals (RIs) for laboratory analyses are an integral part of the process of correct interpretation of clinical laboratory test results. RIs given in laboratory reports have an important role in aiding the clinician in interpreting test results in reference to values for healthy populations. Since the 1980s, the International Federation of Clinical Chemistry (IFCC) has been proactive in establishing recommendations to clarify the true significance of the term ‘RIs, to select the appropriate reference population and statistically analyse the data. The C28-A3 guideline published by the Clinical and Laboratory Standards Institute (CLSI) and IFCC is still the most widely-used source of reference in this area. In recent years, protocols additional to the Guideline have been published by the IFCC, Committee on Reference Intervals and Decision Limits (C-RIDL), including all details of multicenter studies on RIs to meet the requirements in this area. Multicentric RIs studies are the most important development in the area of RIs. Recently, the C-RIDL has performed many multicentric studies to obtain common RIs. Confusion of RIs and clinical decision limits (CDLs) remains an issue and pediatric and geriatric age groups are a significant problem. For future studies of RIs, the genetic effect would seem to be the most challenging area. The aim of the review is to present the current theory and practice of RIs, with special emphasis given to multicenter RIs studies, RIs studies for pediatric and geriatric age groups, clinical decision limits and partitioning by genetic effects on RIs.
Presidential Address, 1974. The more or less startling effects of weak prestimulation.

Weak lead stimulation can modify the human startle reflex It is proposed that, with the aid of physiological measures taken in the interval between lead and startle stimuli, this paradigm offers a promising method of investigating different levels of central processing, the operation of a short time-constant as opposed to a long time-constant system, and the operation of an orienting-Attentional as apposed an Intensity dependent activational system.