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The major constituents of sand are silica and silicates. The facile and low-cost purification technology of silica from natural sand is of magnificent importance to the industrial applications of silicon-based materials. Herein, we report a green, low-cost, and universal method to purify silica from natural sand. Sand from deserts, rivers, and seas is selected as the representative of natural sand. The initial purity of silica is 52.1 wt% for desert sand, 39.3 wt% for river sand, and 35.8 wt% for sea sand. High-purity silica has been successfully separated and purified from natural sand via ball milling, reacting with 30 bar CO2 and hydrochloric acid. The purity of silica derived from natural sand reaches >96 wt%. In this work, the mechanism for the purification of silica from natural sand is discussed. This study provides a new method to separate high-purity silica from natural sand without the generation of toxic and harmful substances.

Background: The assessment of liver fibrosis has been a critical component in the clinical management of liver diseases. We performed a meta-analysis to evaluate serum Golgi protein 73 (GP73) in the diagnosis of liver fibrosis. Methods: A literature search was performed in eight databases until July 13, 2022. We searched strictly studies according to inclusion and exclusion criteria, extracted data, and than assessed quality. We pooled the sensitivity, specificity and other diagnostic estimates of serum GP73 to assess liver fibrosis. Moreover, publication bias, threshold analysis, sensitivity analysis, meta-regression, subgroup analysis and post-test probability were evaluated. Results: Our research integrated 16 articles including 3676 patients. Potential publication bias and threshold effect were not found. The pooled sensitivity, specificity, and area under the curve (AUC) of the summary receiver operating characteristic curve were 0.63, 0.79 and 0.818 for significant fibrosis; 0.77, 0.76 and 0.852 for advanced fibrosis; and 0.80, 0.76 and 0.894 for cirrhosis, respectively. The aetiology was one of important sources of heterogeneity. Conclusion: Serum GP73 was a feasible diagnostic marker for liver fibrosis, which is of great significance for the clinical management of liver diseases.

In this work, we synthesized MnO2/CeO2 electrocatalysts by in situ decoration of α–MnO2 with CeO2 particles during a one-step hydrothermal process. The morphology, composition, and electrochemical properties were studied in the context of application to the oxygen reduction reaction (ORR) and Mg-air battery. According to the results, α–MnO2/CeO2 microfibres exhibited better ORR performance than α–MnO2 microfibres due to the synergistic result between the introduction of Ce3+ in CeO2 lattice and the enhancement of Mn3+ content in MnO2 lattice. α–MnO2/CeO2 microfibres provided a higher surface area and more catalytic active sites than α–MnO2 microfibres by controlling the molar ratio of Ce3+/Mn7+ for the precursor. When the mole ratio of Ce3+ and Mn7+ in the precursors was 10%, the four-electron transfer process of the MnO2/CeO2 microfibres (MC-140-12-10) was found to be similar to that of the 20 wt% Pt/C commercial catalysts. MC-140-12-10 microfibres also showed the excellent long-term stability after 25,000 s and superior Mg–air battery performances than α–MnO2. Hence, the work paves the way for developing Mg-air batteries through a simple synthesis and cost-effective ORR catalyst.

A binder-free AgCl@Ag (SPL-A) cathode was prepared via a facile one-step synthesis by the in situ growth of AgCl active material on the surface of Ag foil substrate. Compared with the AgCl cathode (SPL-B) prepared by the traditional smelting-rolling method, the coarse-grained particulates of AgCl in AgCl@Ag cathode facilitated the permeation of the electrolyte. In addition, it exhibited a preferred growth orientation of the (111), (222), and (311) crystal planes to reduce the charge transfer resistance. The electrochemical behaviors of the optimized SPL-A-24 cathode (prepared with reaction time of 24 h) and the SPL-B cathode were also compared. The galvanostatic discharge results showed that SPL-A-24 cathode had a more positive electrode potential than SPL-B cathode (−0.06 V vs −0.19 V at 50 mA cm−2). Moreover, SPL-A cathode exhibited a stable discharge process that SPL-B cathode could not achieve at 100 mA cm−2 and 250 mA cm−2. The magnesium seawater-activated battery assembled with SPL-A-24 cathode displayed a shorter time to reach the voltage plateau (0.2 s), a higher maximum discharge voltage (1.69 V), a larger specific power (255.5 mWh g−1), and higher specific capacity (167.7 mAh g−1) at the discharge current density of 50 mA cm−2.

Lithium sulfide (Li2S) is considered to be the best potential substitution for sulfur-based cathodes due to its high theoretical specific capacity (1166 mAh g−1) and good compatibility with lithium metal-free anodes. However, the electrical insulation nature of Li2S and severe shuttling of lithium polysulfides lead to poor rate capability and cycling stability. Confining Li2S into polar conductive porous carbon is regarded as a promising strategy to solve these problems. In this work, N-doped porous carbon microspheres (NPCMs) derived from yeasts are designed and synthesized as a host to confine Li2S. Nano Li2S is successfully entered into the NPCMs’ pores to form N-doped porous carbon microspheres–Li2S composite (NPCMs–Li2S) by a typical liquid infiltration–evaporation method. NPCMs–Li2S not only delivers a high initial discharge capacity of 1077 mAh g−1 at 0.2 A g−1, but also displays good rate capability of 198 mAh g−1 at 5.0 A g−1 and long-term lifespan over 500 cycles. The improved cycling and high-rate performance of NPCMs–Li2S can be attributed to the NPCMs’ host, realizing the strong fixation of LiPSs and enhancing the electron and charge conduction of Li2S in NPCMs–Li2S cathodes.

Purpose To describe the ultrasound presentation of the brain and cerebral hemodynamics in neonates with hypoxic-ischemic encephalopathy (HIE) by comparison with control subjects. Material and methods During June 2012 to April 2013, full term neonates who had clinical evidence of HIE were enrolled. Healthy newborns without HIE were used as a control group. Cerebral parenchyma, size of lateral ventricles and hemodynamic parameters of cerebral arteries were studied using two-dimensional duplex and color Doppler ultrasound. Neonates with moderate and severe HIE were followed-up with ultrasound for at least 3 months. Results A total of 158 consecutive neonates (82 boys and 76 girls), including 54 with mild HIE, 60 with moderate HIE and 44 with severe HIE were included. One hundred and twenty healthy newborns were randomly selected as a control group. Abnormal ultrasound findings of brain parenchyma were found in 25/54 (46.3%) neonates with mild HIE whereas they were found in 58/60 (96.7%) neonates with moderate HIE and 44/44 (100%) neonates with severe HIE. Almost all neonates with severe HIE had decreased cerebral artery blood flow velocity and increased resistance index of cerebral arteries. Of the 104 neonates with moderate or severe HIE, follow-up ultrasound examination revealed cystic parenchymal lesions in 12/104 (11.5%), progressive ventricular dilatation and brain atrophy in 12/104 (11.5%), mild ventricular dilatation in 15/104 (14.4%) and leukoencephalomalacia in 2/104 (1.9%) neonates. Conclusion Ultrasound features such as the size of lateral ventricles, altered brain parenchymal echogenicity and cerebral blood flow parameters are useful for the early diagnosis of HIE and help predict outcome.

Objectives We retrospectively studied hemodynamic changes in the interlobar artery to assess the clinical value of color Doppler sonography for detecting preclinical obesity-related nephropathy. Methods Color Doppler renal sonography was performed in 52 children with obesity-related nephropathy and 51 control children with simple obesity. The interlobar artery resistive index (RI) was measured and compared with clinical data and laboratory indicators. Results The left RI (mean ± SD, 0.65 ± 0.05 versus 0.60 ± 0.08; t = 3.85), right RI (0.64 ± 0.03 versus 0.59 ± 0.02; t = 10.00), and mean RI (0.64 ± 0.05 versus 0.59 ± 0.06; t = 5.00) revealed large statistically significant increases in the obesity-related nephropathy group (all P

Multidrug resistance (MDR) is an important issue in current cancer treatments. In human cancer, drug resistance is primarily associated with the overexpression of multidrug resistance gene 1 (MDR1). Therefore, the human MDR1 gene promoter may be a target for anti‑MDR drug screening. Numerous methods to prevent MDR have been investigated. However, they have been proven to be clinically ineffective. Therefore, the aim of the present study was to investigate whether downregulation of nucleophosmin (NPM) demonstrates any effects on the reversal of MDR in hepatocellular carcinoma (HCC) cells. In the present study, two in vitro MDR HCC cell lines, HepG2/Adriamycin (ADM) and SMMC7721/ADM, were established and the level of MDR was measured. The results demonstrated that NPM downregulation markedly reversed the effects of MDR in the model used. In addition, NPM downregulation reduced P-glycoprotein expression, as well as MDR1 expression. These results suggested that downregulation of NPM may be a novel and effective method of reversing the effects of MDR, and may be a potential adjuvant for tumor chemotherapy.

Cubic boron nitride (cBN) powders with different grain size were used as a starting material, and the pure polycrystalline cubic boron nitride (PcBN) samples were sintered under the same conditions at 7GPa, 1700 °C, 270 s. Abrasion resistance and compressive strength of sintered pure PcBN samples were tested, and the microstructure was observed and analyzed by SEM, HRTEM, XRD and Raman spectrum. The results show that the particle size of cBN has not only a great influence on microstructure and property of the sintered pure PcBN un-der the same conditions but also influence on the bonding mechanism of the cBN particles. The inner stress of the pure PcBN sintered with the cBN particle size of 10 μm during the high pressure sintering process is about 199–222% higher than that of the sample with the cBN size of 1 μm. The wear ratio and the compressive strength of PcBN samples sintered with 10 μm cBN was increased by 47.7% and 39.7% than that of the sintered sample with 1 μm cBN respectively. The coarser-grained PcBN contains serious deformation and crushing, which can be attributed to the twin boundary and the stacking faults in the samples. As a consequence, the abrasion ratio and compressive strength of the pure PcBN are dramatically increased. It is assumed that self-bonding mechanism generated from plasticity deformation, which is a main bonding mechanism for the high pressure sintering of pure cubic boron nitride.

We retrospectively studied hemodynamic changes in the interlobar artery to assess the clinical value of color Doppler sonography for detecting preclinical obesity-related nephropathy.Color Doppler renal sonography was performed in 52 children with obesity-related nephropathy and 51 control children with simple obesity. The interlobar artery resistive index (RI) was measured and compared with clinical data and laboratory indicators.The left RI (mean ± SD, 0.65 ± 0.05 versus 0.60 ± 0.08; t = 3.85), right RI (0.64 ± 0.03 versus 0.59 ± 0.02; t = 10.00), and mean RI (0.64 ± 0.05 versus 0.59 ± 0.06; t = 5.00) revealed large statistically significant increases in the obesity-related nephropathy group (all P .01). In the obesity-related nephropathy group, a positive correlation was found between the mean RI and 24-hour urine trace albumin (r = 0.47; P .01), triglycerides (r = 0.98; P .01), and body mass index (r = 0.28; P .05). The 24-hour urine trace albumin and triglycerides were higher in the obesity-related nephropathy group than the control group (P .05). In the control group, a mild positive correlation was also found between the mean RI and body mass index (r = 0.24; P .05).Color Doppler sonography successfully indicated renal hemodynamic changes and has diagnostic value for early-stage obesity-related nephropathy.

We introduce a new factorization algorithm based on the optical computation by multi-path interference of the periodicity of a "factoring" function given by exponential sums at continuous arguments. We demonstrate that this algorithm allows, in principle, the prime number decomposition of several large numbers by exploiting a remarking rescaling property of this periodic function. Such a function is recorded by measuring optical interferograms with a multi-path Michelson interferometer, a polychromatic light source and a spectrometer. The information about factors is encoded in the location of the inteferogram maxima.

We construct an analog computer based on light interference to encode the hyperbolic function f({\zeta}) = 1/{\zeta} into a sequence of skewed curlicue functions. The resulting interferogram when scaled appropriately allows us to find the prime number decompositions of integers. We implement this idea exploiting polychromatic optical interference in a multipath interferometer and factor seven-digit numbers. We give an estimate for the largest number that can be factored by this scheme., Comment: 4 pages, 2 figures

Quantitative dynamic contrast enhanced MRI (DCE-MRI) can offer information related to tumour perfusion and permeability (Ktrans), rate constant (Kep), extravascular extracellular volume fraction (Ve) and distribution volume (Vd). Different types of gadolinium-based contrast agents (GBCAs) may traverse the vascular wall with different velocities owing to their physicochemical characteristics. The purpose of this article was to compare the DCE-MRI quantitative results (Ktrans, Kep, Ve and Vd) between Magnevist and Eovist in a VX2 rabbit liver tumour model. Sixteen rabbits (body weight, 3 Kg; random gender) containing implanted hepatic VX2 carcinomas were randomly divided into two groups based on the regimen of MRI contrast agent administered, eight rabbits in each group. All rabbits underwent a liver DCE-MRscan before tumour transplantation. Fourteen days after tumour transplantation, the eight rabbits in Group A (Magnevist group) underwent a liver DCE-MR scan in a 3.0 T Magnetom Verio MR scanner (Siemens Healthcare, AD, Germany) after the administration of Magnevist at the flow rate of 1 ml s–1. The Group B rabbits underwent the same scan except for the administration of Eovist at the same flow rate. Twenty-four hours after the initial DCE-MRI, repeat DCE-MRI was performed with the cross-over GBCA at the same flow rate in each group. Every rabbit received 0.6 ml GBCA (0.2 ml Kg–1) during each DCE-MRI. Ktrans, Kep, Ve and Vd were measured in the tumour lesion and compared with normal liver tissue in the same slice. A pathologic examination was also performed. Hepatocellular carcinoma was diagnosed in all 16 rabbits by pathologic examination. There were no significant differences in Ktrans, Ve, Kep and Vd between the two groups of rabbits (p > 0.05). The Ktrans, Ve, Kep and Vd of the VX2 rabbit liver tumour model were significantly higher than the normal liver parenchyma (0.742 ± 0.086 vs 0.027 ± 0.002, 7.345 ± 0.043 vs 6.721 ± 0.035, 0.101 ± 0.005 vs 0.101 ± 0.005, 0.419 ± 0.083 vs 0.037 ± 0.005, respectively; p 0.05). In the VX2 rabbit liver tumour model, DCE-MRI performed with different types of GBCA can develop different quantitative results with respect to Ktrans, Ve and Vd. The liver-specific GBCA, Eovist, is more sensitive than the general GBCA, Magnevist, in detecting tumour perfusion and permeability.

A novel supramolecular thin film in which a non-linear optical (NLO) chromophore is uniaxially included in the helical cavity of amylose, revealed a spontaneous self-assembly with a long-range polar order of the chromophores perpendicular to the film surface. This was manifested by a significantly large second harmonic generation (SHG) observed from solution-cast solid supramolecular thin films on a glass substrate without any external field. Such self-assembly/self-poling and the long-term polar stability of the supramolecular chromophores are thought to be due to the helical rigid-rod structure, their dipolar and/or chiral recognition in the ordering process following the polar initiation through the interface interaction of the chromophore with the glass substrate, and H-bonding among the ordered supramolecules.

Picosecond phase conjugation and two-wave coupling in cerium-doped strontium barium niobate at 778 nm were studied. The phase conjugation reflectivity at 778 nm was measured to be R pc = 58%. It is close to that pumped by a continuous-wave pump source. The temporal width t pc and spectral width δγpc of the phase conjugate pulse were measured to be the same as that of the pump pulse. The intensity coupling gain of two-wave coupling as a function of time delay τD between two beams was also studied.

A high reflectivity broad-band SBN : Ce phase conjugator with an external ring cavity in the near infrared wavelength region, 706 to 830 nm, is reported. Phase conjugation reflectivity was measured to be greater than 60% in the wavelength region, 706-820 nm, and as high as 67% at 716 nm. To our knowledge, this is the highest phase conjugation reflectivity by a SBN : Ce self-pumped phase conjugator. Both c.w. and square-wave pump sources were used. No significant changes of the phase conjugation reflectivity were observed when the pump source was changed from c.w. to a square wave at each different wavelength. The wave form of the phase conjugate wave follows the pump square wave. The build-up time of the phase conjugate wave under a square-wave pump was found to be twice that under a c.w. pump when the peak power of the square wave was the same as the power of the c.w. beam.

We exploit the remarkable phenomena of interference in physics together with aspects of number theory in order to factorize large numbers. In particular, the introduction of continuous truncated exponential sums (CTES) allows us to develop a new algorithm for factoring several large numbers by a single measurement of the periodicity of a CTES interferogram. Such an interferogram can be obtained by measuring the interference pattern produced by polychromatic light interacting with an interferometer with variable optical paths.

Using an undoped BaTiO 3 crystal, the reflectivities of the self-pumped phase-conjugate mirror operated in total internal-reflection geometry (TIR) at near infrared wavelengths from 706 to 850 nm were measured. The phase conjugation reflectivities R pc > 50% at 706 to 760 nm, R pc =40% at 816 nm, and R pc =20% at 850 nm were observed. The two-wave coupling exponential gain coefficient Γ and the photorefractive index grating formation rate τ -1 PR as a function of wavelength from 706 to 850 nm were studied. The exponential gain coefficients Γ=11.1 cm -1 at 706 nm and Γ=7.6 cm -1 at 850 nm were obtained. It was also found that the absorption coefficient α in the near infrared wavelengths is much smaller than that in the visible region.

We will describe a new factorization algorithm based on the reproduction of continuous exponential sums, using the interference pattern produced by polychromatic light interacting with an interferometer with variable optical paths. We will describe two possible interferometers: a generalized symmetric Michelson interferometer and a liquid crystal grating. Such an algorithm allows, for the first time, to find all the factors of a number N in a single run without precalculating the ratio N/l, where l are all the possible trial factors. It also allows to solve the problem of ghost factors and to factorize different numbers using the same output interference pattern.

We present the experimental realization of a new Gauss sums factorization algorithm, which, respect to the past realizations, avoids the pre-checking of the trial factors and allows to obtain the factors in a single run.

A new method for measuring electrooptic coefficients of nonlinear crystals has been developed and used to obtain an accurate measurement of r33 and r13 for Strontium Barium Niobate (SBN). An electrooptic modulator was used with a Michelson interferometer for ac modulation (sub-Hz to MHz). By observing the appearance and symmetrical shape of the second harmonic of the ac modulation, the electrooptic coefficients r33 and r13 of SBN were measured with higher accuracy. The unclamped electrooptic coefficients of poled of SrxBa1-xNb2O6 single crystal are: r33=237±3 pm/V and r13=37±1 pm/V, at λ=632.8 nm and T=21°C. In addition the piezoelectric coefficient d23 has been measured with d23=25±5pm/V.

In this paper, we will describe a new factorization algorithm based on the continuous representation of Gauss sums, generalizable to orders j>2. Such an algorithm allows one, for the first time, to find all the factors of a number N in a single run without precalculating the ratio N/l, where l are all the possible trial factors. Continuous truncated exponential sums turn out to be a powerful tool for distinguishing factors from non-factors (we also suggest, with regard to this topic, to read an interesting paper by S. Woelk et al. also published in this issue [Woelk, Feiler, Schleich, J. Mod. Opt. in press]) and factorizing different numbers at the same time. We will also describe two possible M-path optical interferometers, which can be used to experimentally realize this algorithm: a liquid crystal grating and a generalized symmetric Michelson interferometer., 8 pages, 5 figures

Direct two-photon transitions between the crystal field components of the 3H6 ground state and the 1I6 excited state within the 4f12 manifold of Tm3+: LaF3 have been observed at 77 K. The dependence of the induced fluorescence intensity on the pumping laser intensity agrees with the prediction by two-photon absorption theory. Several new crystal field components of 1I6 were observed from the two-photon transitions of the absorption spectra.