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Purpose: Thyroid cancer is one of a set of extrahepatic cancers that closely linked to metabolic dysfunction-associated fatty liver disease (MAFLD). However, the connection between MAFLD and the characteristics of papillary thyroid cancer (PTC) remains unexplored. Methods: Between Jan 2020 and Oct 2022, surgical cases of PTC patients were examined at the first Affiliated Hospital of Wenzhou Medical University. Clinical data extracted from the electronic medical system underwent a rigorous comparison between two groups, classified based on MAFLD criteria, using logistic regression analysis. Results: In this study of 4,410 PTC patients, 18.3% had MAFLD. MAFLD emerged as a distinct risk factor for lymph node metastasis (OR = 1.230, 95% CI 1.018–1.487) in this cohort, especially in females (OR = 1.321, 95% CI 1.026–1.702) and those with BMI ≥ 23 kg/m2(OR = 1.232, 95% CI 1.004–1.511). The presence of MAFLD was found to significantly elevate the risk of BRAF V600Emutation in both subgroups characterized by FIB-4 score ≥ 1.3 (OR = 1.968, 95% CI 1.107–3.496) and BMI < 23 kg/m2(OR = 2.584, 95% CI 1.012–6.601). Moreover, among the subset of individuals without non-alcoholic fatty liver disease (NAFLD), it was noted that MAFLD considerably increased the likelihood of tumor multifocality (OR = 1.697, 95% CI 1.111–2.592). Nevertheless, MAFLD did not exhibit any correlation with increased tumor size, extra-thyroidal extension (ETE), or later TNM stage in PTC. Conclusion: In this cross-sectional study, we discovered a significant association between MAFLD and increased occurrences of lymph node metastasis. Furthermore, MAFLD was linked to a higher chance of BRAF V600Emutation and the presence of multiple tumors in certain subgroups.

Quantum simulation provides platforms to study fundamental aspects of many-body physics in a controlled way, and to explore their implications for quantum technology. However, the dimension of the Hilbert space grows exponentially with the number of interacting particles, which means that investigations of strongly correlated problems such as quantum criticality and many-body localization in terms of few-body probes in real space are often insufficient. Here we demonstrate how to tackle such questions on a superconducting quantum processor from a Fock-space perspective. We map a many-body system onto an unconventional Anderson model on a network of many-body states, which allows the direct observation of wave-packet propagation in Fock space. We find a quantum-critical regime of anomalously enhanced wave-packet width and deduce a critical point from the maximum wave-packet fluctuations, which lends support to the two-dimensional many-body localization transition in finite-sized systems. Our results introduce an alternative picture for characterizing many-body dynamics and for exploring the controversial problems such as criticality and dimensionality. Moreover, the protocol is universal and scalable, and is therefore a promising strategy to solve a broader range of many-body problems on future quantum devices.

Holonomic quantum computing offers a promising paradigm for quantum computation due to its error resistance and the ability to perform universal quantum computations. Here, we propose a scheme for the rapid implementation of a holonomic swap gate in neutral atomic systems, based on the selective Rydberg pumping mechanism. By employing time-dependent soft control, we effectively mitigate the impact of off-resonant terms even at higher driving intensities compared to time-independent driving. This approach accelerates the synthesis of logic gates and passively reduces the decoherence effects. Furthermore, by introducing an additional atom and applying the appropriate driving field, our scheme can be directly extended to implement a three-qubit controlled-swap gate. This advancement makes it a valuable tool for quantum state preparation, quantum switches, and a variational quantum algorithm in neutral atom systems.

Purpose: Numerous biomarkers of diabetic kidney disease (DKD) are associated with renal prognosis but head-to-head comparisons are lacking. This study aimed to examine the association of soluble tumor necrosis factor receptor type 1 (sTNFR1), fibroblast growth factor 21 (FGF-21), endocan, N-terminal pro-brain natriuretic peptide (NT-pro-BNP), and renal outcomes of patients with or without clinical signs of DKD. Methods: A total of 312 patients were enrolled in a prospective observational study that excluded individuals with estimated glomerular filtration rates (eGFR) < 30 mL/min/1.73 m2. Composite renal outcomes included either a > 30% decline in eGFR and worsening albuminuria or both from consecutive tests of blood/urine during a 3.5-year follow-up period. Results: Higher sTNFR1 and FGF-21, rather than endocan and NT-pro-BNP, levels were associated with renal outcomes but the significance was lost after adjusting for confounders. However, sTNFR1 levels ≥ 9.79 pg/dL or FGF-21 levels ≥ 1.40 pg/dL were associated with renal outcomes after adjusting for the confounders (hazard ration [HR] 2.76, 95% confidence interval [CI] 1.36–5.60, p= 0.005 for sTNFR1 level; HR 1.95, 95% CI 1.03–3.69, p= 0.03 for FGF-21 level). The combination of both levels exhibited even better association with renal outcomes than did either one alone (adjusted HR 4.45, 95% CI 1.86–10.65, p= 0.001). The results were consistent among patients with preserved renal function and normoalbuminuria. Conclusion: Both sTNFR1 and FGF-21 levels were associated with renal outcomes of in patients with type 2 diabetes, and the combination of the abovementioned markers exhibits better predictability.

Supplemental Digital Content is available in the text.

Abstract: In this work, we have developed a near-infrared emissive polyethyleneimine capped Ag2(PEI-Ag2S QD) quantum dots based chemosensor for sensing trace-level Hg2+in water by taking advantage of the metal-induced aggregation strategy. The fluorescence determination of Hg2+by PEI-Ag2S QD at different pH (pH 4, 7, and 10) were performed, respectively. Under the optimum conditions, the selectivity of this system for Hg2+over other metal ions in aqueous solutions was remarkably high, and its detection limits was 0.5 nM at pH 4. In addition, the present approach provides the advantages of rapidity, simplicity, low background and low cost. The assay also offers great potential for specific detection of Hg2+in real water samples. This developed PEI-Ag2S QD-based method presages more opportunities for application in environmental systems.

New research suggests low levels of substance P--a nerve cell signaling molecule found in tears--may indicate an increased risk of diabetic corneal neuropathy. After measuring substance P levels in the [...]

Current donor management practices target macrohaemodynamic parameters, but it is unclear if this leads to improvements in microvascular perfusion and tissue oxygenation; the latter may have more impact on organ status. In a recent preclinical study we determined that brain death impaired tissue perfusion and oxygen utilisation in swine while pharmacologic correction of these deficits improved organ function and reduced markers of tissue injury. As a first step in translating the preclinical findings, we conducted a prospective observational study to determine if there was an association between peripheral tissue oxygenation (measured by near-infrared spectroscopy) in deceased by neurological criteria human donors and the number of organs transplanted. In 60 donors, the mean time-weighted average of tissue oxygenation was 87.5% (standard deviation, SD, 5.2%) and the average number of organs transplanted was 3.5 (SD 2); there was a positive linear relationship between these two parameters. A 5% rise in tissue oxygenation was associated with an increase of 0.47 organs transplanted (95% confidence intervals 0.16 to 0.78) after adjusting for age (P=0.004). No such correlations were observed for the macrohaemodynamic or macro-oxygenation parameters (including arterial blood oxygenation). The results of this clinical trial are consistent with our preclinical work and support the postulate that targeting the microvasculature to improve tissue perfusion and tissue oxygen delivery in human donors has the potential to increase the quantity of organs suitable for transplant.

Kagome magnets have garnered a lot of investigation due to their plentiful topological states and promising, strong correlated phenomena. However, there have been few reports of two-dimensional (2D) van der Waals kagome magnets. Here, we suggest a stable 2D van der Waals kagome material, V3Br8, which exhibits a ferromagnetic ground state with a Curie temperature of 89 K. Near the Fermi level, there is only a set of three kagome bands from one spin species, which possesses Van Hove singularities at the Mpoint and a Weyl point at the Kpoint. It is interesting that its ground state is gapless at the Kpoint and maintains a 2D Weyl half semimetal state even in the presence of spin-orbit coupling, while when the magnetization rotates from the in-plane direction of the ground state to the out-of-plane direction, the spin-orbit coupling will open an energy gap at the Kpoint, resulting in a topological phase transition to a quantum anomalous Hall effect state. We further demonstrate that the tensile strain can optimize the band structure and raise the Curie temperature to above 100 K. In addition, a Li atom intercalated V3Br8(V3Br8Li) is revealed to be a stable structure that can successfully tune the Fermi level to the Weyl point while maintaining the ferromagnetic ground state. Moreover, V3Br8Li displays an out-of-plane magnetism, producing the quantum anomalous Hall effect . Our findings provide a solid foundation for future research into topological states and singular effects in 2D kagome magnets.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy, and T-ALL patients are prone to early disease relapse and suffer from poor outcomes. The PTEN, PI3K/AKT and Notch pathways are frequently altered in T-ALL. PTEN is a tumor suppressor that inactivates the PI3K pathway. We profiled miRNAs in Pten-deficient mouse T-ALL and identified miR-26b as a potentially dysregulated gene. We validated decreased expression levels of miR-26b in mouse and human T-ALL cells. In addition, expression of exogenous miR-26b reduced proliferation and promoted apoptosis of T-ALL cells in vitro, and hindered progression of T-ALL in vivo. Furthermore, miR-26b inhibited the PI3K/AKT pathway by directly targeting PIK3CD, the gene encoding PI3Kδ, in human T-ALL cell lines. ShRNA for PIK3CDand CAL-101, a PIK3CD inhibitor, reduced the growth and increased apoptosis of T-ALL cells. Finally, we showed that PTEN induced miR-26b expression by regulating the differential expression of Ikaros isoforms that are transcriptional regulators of miR-26b. These results suggest that miR-26b functions as a tumor suppressor in the development of T-ALL. Further characterization of targets and regulators of miR-26b may be promising for the development of novel therapies.

Aims.Stellar spots produce periodic variations in photometric data. We aim to determine the observed periods with a high accuracy to improve measurements of stellar differential rotation.

We applied the method of three-stage weighted multichannel period analysis (MPA) to photometric observations of HN Peg obtained in 1992–99. We detected two periods: the longer one stayed almost constant near 5$\fd$1 but appeared only during the observing seasons in 1993–98, while the shorter one was present for all observing seasons, having fluctuations within .
If the two periods are interpreted as caused by differential rotation, we may have detected two distinct latitude zones of spot activity, one where spots were confined to within a very narrow range of latitude, and another where the latitude range may be somewhat broader. The existence of two latitude zones of activity in this young solar analogue closely matches what is seen in the Sun. However, the presence of two periods may also be caused by long-lived active areas moving in longitude.
We use HN Peg as a test case for our new MPA statistical method. Because of the limited quality of the data and the complexity of stellar activity our results are tentative, leaving space also for other interpretations.

In this paper we continue the research on the Cerenkov origin of the iron Kαline in AGNs. We claim again that the newly recognized line emission mechanism, Cerenkov line-like radiation, could be significantly responsible for the observed iron K-lines of AGNs. We give a new model calculation of the luminosity of the iron Kαline in the optically thin condition, which is an important extension of our previous calculation in the optically thick case. The new calculation is also comparable to the typical observed luminosity of iron Kαline, thus confirming the effectiveness of the new mechanism. Besides, we analyze a possible negative influence of the hydrogen-dominated plasma upon the efficiency of Cerenkov line-like radiation in detail, which was ignored in our previous paper (You et al. [CITE]). We conclude that such a negative effect of the plasma oscillation is unimportant and can be neglected.

The original Kompaneets equation fails to describe down-Comptonization, which is the most important radiative transfer process in hard X-ray and γ-ray astronomy, compared with up-Comptonization. In this paper, we improve our previous derivation of the extended Kompaneets equation and present it more clearly. The new equation can be used to describe a more general Comptonization process, including up- and down-Comptonization, suitable for any case, $h\overline{\nu}\ll kT_{\mathrm e}$, $h\overline{\nu}\gg kT_{\mathrm e}$and $h\overline{\nu}\sim kT_{\mathrm e}$. The condition of the original Kompaneets equation $h\overline{\nu}\ll kT_{\mathrm e}$is no longer necessary. Using the extended equation, we give some typical solutions in X-ray astronomy, and compare them with those of the prevailing Monte Carlo simulations and the Ross-McCray equation. The excellent consistency between the extended Kompaneets equation and Monte Carlo simulation or Ross-McCray equation confirms the correctness of our extended Kompaneets equation. The numerical solution of the extended Kompaneets equation is less expensive in terms of computational time than the Monte Carlo simulation. Another advantage of the equation method is the simplicity and the clarity in physics. The potential applications in X-ray and γ-ray astronomy are also emphasized.

Biodegradable sheath-core structured nanofibers, with chitosan as the sheath material and polylactide (PLA) at the core, were developed for the removal of metal ions. For the electrospinning of sheath-core nanofibers, predetermined weight percentages of chitosan were first dissolved in trifluoroacetic acid (TFA) with sonication for 30 min, and then mixed by a magnetic stirrer for 12 h. The same procedure was conducted with polylactide (PLA). The chitosan and polylactide solutions were then fed into two different capillary tubes with needles of small diameter, respectively, for co-axial electrospinning. The delivery rates of the solutions were controlled by two independent pumps for the sheath chitosan solutions and the core PLA solution. The morphology of the electrospun nanofibers was examined by a scanning electron microscope (SEM). The average diameter of the electrospun nanofibers was found to range from 234 nm to 562 nm. The influence of various process conditions on the metal removal was also investigated. The removal efficiency of the sheath-core chitosan/PLA nanofibers was measured and compared with the efficiency of blended chitosan/PLA nanofibers. The experimental results suggested that the electrospun sheath-core nanofibers exhibited superior metal ion removal efficiency compared to the blended nanofibers. The removal efficiency of the nanofibrous membranes increased with the initial metal ion concentrations and the pH value and decreased with the temperature of the solutions.

We have proposed here a facile, simple, and cost-effective turn-on assay for melamine with carbon nanodots (C-dots) as a fluorescence reader. Melamine is prone to coordinate with Hg2+due to the presence of a multi-nitrogen heterocyclic ring. This property is the cause for the anti-quenching ability of Hg2+to C-dots through decreasing the interaction between Hg2+and C-dots. By this method, a detection limit of 0.3 μM is obtained, which is approximately 65 times lower than that of the US Food and Drug Administration estimated melamine safety limit of 20 μM. In addition, several real samples including raw milk and milk powder are analyzed using the sensing system with satisfactory recoveries. This research may expand the applications of C-dots as the fluorescent probe in food safety.

We find dynamical invariants for open quantum systems described by the non-Markovian quantum-state-diffusion (QSD) equation. In stark contrast to closed systems where the dynamical invariant can be identical to the system density operator, these dynamical invariants no longer share the equation of motion for the density operator. Moreover, the invariants obtained with a biorthonormal basis can be used to render an exact solution to the QSD equation and the corresponding non-Markovian dynamics without using master equations or numerical simulations. Significantly we show that we can apply these dynamical invariants to reverse engineering a Hamiltonian that is capable of driving the system to the target state, providing a different way to design control strategy for open quantum systems. [ABSTRACT FROM AUTHOR]

The Hei10 830 Åspectra observed in the impulsive phase of the 2N/X20 solar limb flare of 16 August 1989 show unusually broad profiles, and most of the profiles are blue-shifted and/or blue asymmetric with full-width-at-half-maximum (FWHM) greater than 10 Å. Contrary to prominences, weak post-flare loops and surges, the observed profiles of the flare cannot be simulated by Doppler broadening with a uniform flaring atmosphere model. Calculations show that only when the electron density is greater than 1016cm-3 can Stark broadening produce an obvious influence on the Hei10 830 Åprofile. This indicates that it is not plausible that Stark broadening leads to the observed profiles even though they can be fitted by Stark broadening. Alternatively, an expanding flaring atmosphere can perfectly simulate all the observed Hei10 830 Åprofiles. The expanding velocities are generally several tens of km s-1 and that corresponding to the widest profile is greater than 120 km s-1. Expanding velocity and other parameters vary with time and the observed area. This expanding flaring atmosphere model is a perspective candidate for line broadening. It is an indication of the lateral expansion resulting from rapid chromospheric heating in addition to the upward evaporation and downward condensation.

The method of three stage weighted period analysis is generalized for simultaneous multichannel observations. The new method is based on the phase dispersion minimization over all channels simultaneously. The three stages in the full algorithm are phase dispersion minimization method (PDM), linear modeling (LM) and nonlinear modeling (NLM). Simple computational tests of the multichannel period analysis (MPA) are presented. We show that the method has advantages if compared with methods where single channels are analysed separately. We derive a general formula for spurious periods and demonstrate that the interpretation of peaks in the PDM spectra can be more complicated than in classical power spectra.

Quantum theory imposes fundamental limitations on the amount of information that can be carried by any quantum system. On the one hand, the Holevo bound rules out the possibility of encoding more information in a quantum system than in its classical counterpart, comprised of perfectly distinguishable states. On the other hand, when states are uniformly distributed in the state space, the so-called subentropy lower bound is saturated. How uniform quantum systems are can be naturally quantified by characterizing them as t-designs, with t = #8734; corresponding to the uniform distribution. Here we show the existence of a trade-off between the uniformity of a quantum system and the amount of information it can carry. To this aim, we derive a hierarchy of informational bounds as a function of t and prove their tightness for qubits and qutrits. By deriving asymptotic formulas for large dimensions, we also show that the statistics generated by any t-design with t > 1 contains no more than a single bit of information, and this amount decreases with t. Holevo and subentropy bounds are recovered as particular cases for t = 1 and t = ∞, respectively. [ABSTRACT FROM AUTHOR]

A wide class of exact master equations for a multiple qubit system can be explicitly constructed by using the corresponding exact non-Markovian quantum-state diffusion equations. These exact master equations arise naturally from the quantum decoherence dynamics of qubit system as a quantum memory coupled to a collective colored noisy source. The exact master equations are also important in optimal quantum control, quantum dissipation, and quantum thermodynamics. In this paper, we show that the exact non-Markovian master equation for a dissipative V-qubit system can be derived explicitly from the statistical average of the corresponding non-Markovian quantum trajectories. We illustrated our general formulation by an explicit construction of a three-qubit system coupled to a non-Markovian bosonic environment. This multiple qubit master equation offers an accurate time evolution of quantum systems in various domains, and paves the way to investigate the memory effect of an open system in a non-Markovian regime without any approximation. [ABSTRACT FROM AUTHOR]

Statins are thought to potentially impair glucose metabolism, increasing plasma glucose concentration. The effect of prolonged statin use on glucose metabolism among outpatients is thus well established. However, the impact of statin use on glucose concentrations and insulin requirements during surgery remains poorly characterised and may very well differ considering the substantial hyperglycaemic stress response to surgery. We conducted a study to test the hypothesis that patients taking statins preoperatively require more intraoperative insulin than non-users. We analysed 173 adults having major non-cardiac surgery who participated in the Dexamethasone, Light Anaesthesia and Tight Glucose Control Trial between 2007 and 2010. We compared statin and non-statin users on total amount of intraoperative insulin to maintain plasma glucose concentration within 4.4 to 6.1 mmol/l using the inverse propensity score weighting method. Sixty-seven patients were statin users and 106 were non-statin users. The estimated ratio of geometric means between the statin users and the non-users was 1.45 (95% confidence interval: 0.93, 2.26, statin versus non-statin, P=0.11). The total amount of intraoperative insulin usage did not differ significantly among patients taking different types of statins (P=0.50). While the total amount of intraoperative insulin used was not statistically different between the statin users and non-users, we observed a potentially important trend toward insulin resistance intraoperatively among statin users during major non-cardiac surgery. This result is consistent with non-operative settings and cardiac surgery. Further investigation is essential to determine whether this effect is real and, if so, determine which specific statins are more associated with insulin resistance.

Background:The processing of proprotein convertase (PC)-mediated neuropeptide plays a very important role in carcinogenesis and tumor proliferation. Aim:To investigate proneuropeptide processing mechanism in tumorigenesis and tumor proliferation. Materials and methods:The expression and processing profiles of PC1, carboxypeptidase E (CPE), PC2, GHRH, or neuropeptide Y (NPY) gene and protein level were investigated between 42 human breast tumor tissues and 21 tumor-adjacent normal tissues. Results:Gene analyses indicated that the proPC1, CPE, or preproNPYgene had higher expression in the breast tumor tissues, whereas the proPC2or preproGHRHgene showed lower expression in the tissues. Protein analyses showed that the proPC1, PC1, CPE, GHRH, and preproNPY proteins were up-regulated in the tumor tissues, whereas the proPC2, PC2, preproGHRH, and NPY proteins were down-regulated in them. The tissue results were highly corroborated with the serum data from the tumor patients and healthy women. Conclusions:The higher PC1 and CPE expressions as well as the transformation of more proGHRH into active GHRH peptide suggest stronger PC1/CPE-mediated neuropeptide processing in the tumor, whereas the lower PC2 expression as well as the transformation of less proNPY into active NPY peptide suggests a weak PC2-mediated processing in it. The alterations of the convertase expressions and processing show that there is a differential proprotein processing system in the tumor, which leads to the abnormal distributions of species, ratio, and concentration of (pro)peptide(s) in the microenvironment of cells. The latter may contribute to cancer progression.

Non-Markovian quantum state diffusion (NMQSD) provides a powerful approach to the dynamics of an open quantum system in bosonic environments. Here we develop a NMQSD method to study the open quantum system in fermionic environments. This problem involves anticommutative noise functions (i.e., Grassmann variables) that are intrinsically different from the noise functions of bosonic baths. We obtain the NMQSD equation for quantum states of the system and the non-Markovian master equation. Moreover, we apply this NMQSD method to single- and double-quantum-dot systems. [ABSTRACT FROM AUTHOR]

Strained InGaAlP/In0.5Al0.5P multiple quantum wells (MQWs) with digital alloy wells made of alternating 3-monolayer In0.5Ga0.5P and 2-monolayer In0.5Al0.5P layers were grown by using molecular-beam epitaxy. The electronic subband energy states and the interband transition energies of the InGaAlP/InAlP MQWs were calculated by using the finite element method to solve the Schrodinger equation in an 8-band envelope function approximation including the strain effects. The calculated interband transitions of the InGaAlP/InAlP MQWs were in reasonable agreement with the excitonic transitions obtained from the photoluminescence spectra.

A new statistical model was developed for the normal and tangential contact parameters of rough surfaces based on the elastic—plastic contact theory of asperity. Four deformed regimes of fully elastic, first elastoplastic, second elastoplastic, and fully plastic of an asperity contacting with a rigid surface were taken into account by this model. The present model reveals that the normal and tangential contact parameters of rough surfaces are determined by the material properties of rough surface, statistical parameters for surface topography, and loading. Based on the results comparison and analysis, the present model is shown to be more complete than the GW, CEB, ZMC, and CEB friction models in describing the elastic—plastic contact problems between the rough surfaces. The effects of height distribution of asperities, plasticity index, and loading on contact parameters were simulated and discussed. In addition, the Gaussian numerical results predicted by the present model were researched emphatically.

Nano structures such as CNTs were proposed to be directly used as cutting grains to fully utilize the nice mechanical and thermal properties for nano machining. To further understand the CNT abrasive tool, a theoretical study of the CNT uncut chip model was conducted together with preliminary experimental tests to investigate the chip generation in the nano machining process. We found that the CNT distribution was not even in the CNT layer of the wheel. Based this finding, a grain spacing model and a feed of workpiece per cutting edge model were developed. Theoretical results were all very small. It was also found that individual workpiece chips were difficult to find due to small sizes. Further work is necessary. Furthermore, Chip gelling effect was found. The reasons were due to agglomeration and epoxy melting. Experimental results were found agree with our theoretical results.

Wurtzite ZnO has many potential applications in optoelectronic devices, and the hydrogenated ZnO exhibits excellent photoelectronic properties compared to undoped ZnO; however, the structure of H-related defects is still unclear. In this article, the effects of hydrogen-plasma treatment and subsequent annealing on the electrical and optical properties of ZnO films were investigated by a combination of Hall measurement, Raman scattering, and photoluminescence. It is found that two types of hydrogen-related defects, namely, the interstitial hydrogen located at the bond-centered (HBC) and the hydrogen trapped at a O vacancy (HO), are responsible for the n-type background conductivity of ZnO films. Besides introducing two hydrogen-related donor states, the incorporated hydrogen passivates defects at grain boundaries. With increasing annealing temperatures, the unstable HBCatoms gradually diffuse out of the ZnO films and part of them are converted into HO, which gives rise to two anomalous Raman peaks at 275 and 510 cm−1. These results help to clarify the relationship between the hydrogen-related defects in ZnO described in various studies and the free carriers that are produced by the introduction of hydrogen.

A static friction model for elastic-plastic contacting fractal surfaces was proposed based on the modified Majumdar and Bhushan (MB) model. In this model, four regimes were taken into account: fully elastic, first elastoplastic, second elastoplastic, and fully plastic of a deformed asperity contacting with a rigid surface. The work reveals that the static friction coefficient is determined by the material properties of rough surfaces, the fractal parameters for surface topography, and the normal load. Especially, from the results comparison and analysis, it was found that the present model is more complete than the MB model in describing the elastic-plastic contacting fractal surfaces, and the results of the real contact area and the static friction coefficient predicted by the model are larger than those by the MB model for a range of fractal parameters studied. In addition, the results also show that the effect of the normal load on the static friction coefficient is contrary to that by the Chang, Etsion, and Bogy (CEB) friction model.

Dissolved oxygen (DO) concentration is one of the most important factors affecting microbial cell growth and metabolite formation. In this study, a novel two‐stage oxygen supply control strategy was applied to enhance oxygen transfer and promote the ability of arachidonic acid production by Mortierella alpinaME‐1. Based on process analysis, a two‐stage oxygen supply control strategy was proposed in arachidonic acid production in which n‐hexadecane was added as an oxygen vector with a final concentration of 4 % at the first of cultivation, the agitation speed was controlled at 180 rpm in the first 96 h, and then switched to 100 rpm. This strategy was experimentally proven to be successful in arachidonic acid fermentation, relatively high arachidonic acid production (15.9 g/L) and dry cell weight (42.5 g/L) was achieved by applying this strategy. The arachidonic acid productivity (2.27 g/L/d) was also successfully improved by 50.3 % and 28.9 %, respectively, compared with fermentations in which agitation speed was kept constant at 180 rpm and under a two‐stage agitation speed control strategy.

We propose to use nano structures directly to fully utilize the nice mechanical and thermal properties for nano machining. In this project, CNTs were directly used as cutting grains. For the CNT grains, we use epoxy as one of the bonding materials of our choice. A series of CNT grinding wheels were fabricated to demonstrate the effectiveness of the proposed new type of abrasive tool. Preliminary experimental tests were conducted for the proposed method of abrasive tool making. The CNT wheels are made of 1% MWCNTs or Multi Wall CNTs. Preliminary test results show that CNT wheels without functionalization or chemical treatment give the best average results. In the developed abrasive tool, CNT nano cutting edges are clearly seen in the TEM image. Carbon nanotubes can be used as cutting grains for nano machining. Further experiments are necessary.

Aims. Stellar spots produce periodic variations in photometric data. We aim to determine the observed periods with a high accuracy to improve measurements of stellar differential rotation. Methods. We applied the method of three-stage weighted multichannel period analysis (MPA) to photometric observations of LQ?Hydrae obtained in 1992?2000. Results. We detected two periods in 10/1993-5/1994, two periods in 10/1998-6/1999, and three periods in 10/1999-3/2000. The primary period was found to be present for all observing seasons with small fluctuations within 1[Formula: see text][Formula: see text]60?1[Formula: see text][Formula: see text]61, while including the additional secondary periods, the fluctuations become three times larger within 1[Formula: see text][Formula: see text]585?1[Formula: see text][Formula: see text]625. We also found that the amplitudes of the model curves of the primary period varied and reached their maxima in 10/1993-5/1994 and their minima in 10/1997-6/1998, while the amplitudes of the additional periods were always below the amplitudes of the primary period in the same season. Conclusions. We conclude that the stellar spots responsible for the photometric variations of the primary period are long-lived and change their positions between two latitudes corresponding to two different rotation periods of 1[Formula: see text][Formula: see text]60 and of 1[Formula: see text][Formula: see text]61 (or have slightly varying longitude migration rates). The constancy of the primary period in the individual seasons means a constancy of latitude over the observation time intervals. We interpret the appearance of the additional periods to be caused by the formation of new surface structures at different latitudes. The surface structure is thus temporary. Based on our detected period range, the corresponding latitudinal differential rotation rate ??/ ?= 0.025 is small compared with that of the Sun (??/ ?= 0.2).

In pH 3.5 Britton—Robinson buffer solution double-stranded (ds) DNA can react with malachite green (MG) to form an interaction complex, which resulted in the decrease of the electrochemical response of MG, MG had a well-defined second-order derivative linear sweep voltammetric peak at −0.73 V (vs. SCE). After the addition of dsDNA into MG solution, the reductive peak current decreased with the positive shift of peak potential, which was the typical characteristic of intercalation. Based on the interaction, an indirect electrochemical determination method for dsDNA was established. The optimum conditions for the reaction were investigated and there were little or no interferences from the commonly coexisting substances. The decrease of peak current was linear with the concentration of dsDNA over the range of 0.8–12.0 µg cm−3 with the linear regression equation as ΔI p″/nA = 91.70 C/(µg cm−3) + 74.55 (n = 10, γ = 0.990). The detection limit was calculated as 0.46 µg cm−3 (3σ). The method had high sensitivity and was further applied to the dsDNA synthetic samples with satisfactory result. The interaction mechanism was discussed with the intercalation of DNA-MG to form a supramolecular complex and the stoichiometry of the supramolecular complex was calculated by electrochemical method with the binding number 3 and the binding constant 2.35 × 1015 (mol dm−3)−3.

Background: Elderly patients with acute myeloid leukemia (AML) generally have an unfavorable clinical course and are under-represented in clinical trials. The aim of this study was to analyze the prognosis and treatment outcome of elderly AML patients.

Summary A total of 94 actinomycete strains were isolated from the marine sediments of a shrimp farm, 87.2% belonged to the genus Streptomyces, others were Micromonospora spp. Fifty-one percent of the actinomycete strains showed activity against the pathogenic Vibrio spp. strains. Thirty-eight percent of marine Streptomyces strains produced siderophores on chrome azurol S (CAS) agar plates. Seven strains of Streptomyces were found to produce siderophores and to inhibit the growth of Vibrio spp. in vitro. Two of them belonged to the Cinerogriseus group, the most frequently isolated group of Streptomyces. The results showed that streptomycetes could be a promising source for biocontrol agents in aquaculture.

In this paper, Novikov's inversion formula of the attenuated two-dimensional (2D) Radon transform is applied to the reconstruction of attenuated fan-beam projections acquired with equal detector spacing and of attenuated cone-beam projections acquired with a flat planar detector and circular trajectory. The derivation of the fan-beam algorithm is obtained by transformation from parallel-beam coordinates to fan-beam coordinates. The cone-beam reconstruction algorithm is an extension of the fan-beam reconstruction algorithm using Feldkamp–Davis–Kress's (FDK) method. Computer simulations indicate that the algorithm is efficient and is accurate in reconstructing slices close to the central slice of the cone-beam orbit plane. When the attenuation map is set to zero the implementation is equivalent to the FDK method. Reconstructed images are also shown for noise corrupted projections.