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Over 5000 tonnes of gold were accumulated in the Jiaodong Peninsula at the early Cretaceous, the sources and critical ore-forming processes of which are still controversial. Here, we conducted comprehensive in-situ textural, elemental and isotopic analyses on pyrite and gold grains from the different mineralization styles, hydrothermal stages and depths for three representative gold deposits (Linglong, Xiadian and Jiangjiayao) from the northwestern Jiaodong Peninsula, with the aim to exactly constrain the sources and ore-forming processes. Three groups of δ34Spyrite were identified in the studied deposits, of which the Group 1 shows stable and low δ34S (4.8–7.6‰) throughout the hydrothermal evolution while the Group 2 has elevated δ34S (6.0–12.8‰) coupled with increasing As and Au concentrations. The Group 3 shows moderate δ34S (5.2–9.8‰) accompanied by high Al and Si concentrations. The Group 1 suggests a low-δ34S primary auriferous fluid derived from a mantle-related source, whereas the Group 2 indicates the primary auriferous fluid leaching additional S, As and Au from the Precambrian metasedimentary rocks along pathway. The Group 3 is petrographically coupled with numerous silicate inclusions, indicating enhanced fluid-rock interaction between the auriferous fluids and the granitic wallrcoks. Gold fineness decreases from the early to the late hydrothermal stages, combined with increasing deposition of polymetallic sulfides, suggesting an increase of pH resulting in efficient Au deposition. Gold fineness and Bi concentrations in pyrite decrease with shallowing, suggesting that cooling affected Au deposition as well. Bismuth-Te-S minerals were identified in the deep depths, combined with the well correlated Bi and Ag, implying that Bi-Te complexes might play a role in transporting Au and Ag at high-temperature conditions. The above results corroborate that multiple sources and ore-forming processes were responsible for the giant gold mineralization, of which the gold endowment from Precambrian wallrocks needs to be further concerned.

In this paper, we define a notion of β-dimensional mean oscillation of functions u : Q 0 ⊂ ℝ d → ℝ {u:Q_{0}\subset\mathbb{R}^{d}\to\mathbb{R}} which are integrable on β-dimensional subsets of the cube Q 0 {Q_{0}} : ∥ u ∥ BMO β ⁢ ( Q 0 ) := sup Q ⊂ Q 0 ⁡ inf c ∈ ℝ ⁡ 1 l ⁢ ( Q ) β ⁢ ∫ Q | u - c | ⁢ 𝑑 ℋ ∞ β , \displaystyle\|u\|_{\mathrm{BMO}^{\beta}(Q_{0})}\vcentcolon=\sup_{Q\subset Q_{% 0}}\inf_{c\in\mathbb{R}}\frac{1}{l(Q)^{\beta}}\int_{Q}|u-c|\,d\mathcal{H}^{% \beta}_{\infty}, where the supremum is taken over all finite subcubes Q parallel to Q 0 {Q_{0}} , l ⁢ ( Q ) {l(Q)} is the length of the side of the cube Q, and ℋ ∞ β {\mathcal{H}^{\beta}_{\infty}} is the Hausdorff content. In the case β = d {\beta=d} we show this definition is equivalent to the classical notion of John and Nirenberg, while our main result is that for every β ∈ ( 0 , d ] {\beta\in(0,d]} one has a dimensionally appropriate analogue of the John–Nirenberg inequality for functions with bounded β-dimensional mean oscillation: There exist constants c , C > 0 {c,C>0} such that ℋ ∞ β ⁢ ( { x ∈ Q : | u ⁢ ( x ) - c Q | > t } ) ≤ C ⁢ l ⁢ ( Q ) β ⁢ exp ⁡ ( - c ⁢ t ∥ u ∥ BMO β ⁢ ( Q 0 ) ) \displaystyle\mathcal{H}^{\beta}_{\infty}(\{x\in Q:|u(x)-c_{Q}|>t\})\leq Cl(Q)% ^{\beta}\exp\biggl{(}-\frac{ct}{\|u\|_{\mathrm{BMO}^{\beta}(Q_{0})}}\biggr{)} for every t > 0 {t>0} , u ∈ BMO β ⁢ ( Q 0 ) {u\in\mathrm{BMO}^{\beta}(Q_{0})} , Q ⊂ Q 0 {Q\subset Q_{0}} , and suitable c Q ∈ ℝ {c_{Q}\in\mathbb{R}} . Our proof relies on the establishment of capacitary analogues of standard results in integration theory that may be of independent interest.

Secondary hydrothermal reworking of REEs has been widely documented in carbonatites/alkaline rocks, but its potential role in the REE mineralization associated with these rocks is currently poorly understood. This study conducted a combined textural and in situ chemical investigation on the REE mineralization in the ~430 Ma Miaoya carbonatite-syenite complex, central China. Our study shows that the REE mineralization, dated at ~220 Ma, is characterized by a close association of REE minerals (monazite and/or bastnäsite) with pervasive carbonatization overprinting the carbonatites and syenites. In these carbonatites and syenites, both the apatite and calcite, which are the dominant magmatic REE-bearing minerals, exhibit complicated internal textures that are generally composed of BSE-bright and BSE-dark domains. Under BSE imaging, the former domains are homogeneous and free of pores or mineral inclusions, whereas the latter have a high porosity and inclusions of monazite and/or bastnäsite. In situ chemical analyses show that the BSE-dark domains of the apatite and calcite have light REE concentrations and (La/Yb)N values much lower than the BSE-bright areas. These features are similar to those observed in metasomatized apatite from mineral-fluid reaction experiments, thus indicating that the BSE-dark domains formed from primary precursors (i.e., represented by the BSE-bright domains) through a fluid-aided, dissolution-reprecipitation process during which the primary light REEs are hydrothermally remobilized. New, in situ Sr-Nd isotopic results of apatite and various REE minerals, in combination with mass balance calculations, strongly suggest that the remobilized REEs are responsible for the subsequent hydrothermal REE mineralization in the Miaoya complex. Investigations of fluid inclusions show that the fluids responsible for the REE mobilization and mineralization are CO2-rich, with medium temperatures (227–340 °C) and low salinities (1.42–8.82 wt‰). Such a feature, in combination with C-O isotopic data, indicates that the causative fluids are likely co-genetic with fluids from coeval orogenic Au-Ag deposits (220–200 Ma) in the same tectonic unit. Our new findings provide strong evidence that the late hydrothermal upgrading of early cumulated REEs under certain conditions could also be an important tool for REE mineralization in carbonatites, particularly for those present in convergent belts where faults (facilitating fluid migration) and hydrothermal fluids are extensively developed.

We leverage the supervised and semi-supervised Volterra nonlinear equalizers (VNLE) to mitigate the system nonlinearity. Two methods are employed to estimate the coefficients: ordinary least square (OLS) estimator and the least absolute shrinkage and selection operator (Lasso). Due to the additional coupling loss and higher propagation loss in bad weather conditions, FSO-fiber link requires a more stringent power budget. Higher modulation depth and transmitter output power can improve the link budget but need to make nonlinearity correction. Thus, we comprehensively perform a proof-of-concept demonstration in a fiber-FSO converged link with pulse amplitude modulation (PAM). Compared with conventional supervised VNLE using OLS, the coefficients estimated from Lasso require a smaller training symbol overhead. In both the 50-Gbaud PAM4 (at the 1.22 × 10−2 threshold) and 35-Gbaud PAM8 (at the 2 × 10−2 threshold) cases, when the labeled data proportion is 5%, supervised VNLE using Lasso exhibits a received optical power (ROP) improvement up to 3 dB, compared to supervised VNLE using OLS. Moreover, the semi-supervised method can utilize the unlabeled data and further improve the performance without adding signal overhead to the system. In our 50-Gbaud PAM4 experiment, with 60% unlabeled data, the semi-supervised VNLE based on the soft decision (SD) and Lasso demonstrates up to 3-dB sensitivity gain at the BER threshold of 4.5 × 10−3 compared with the supervised VNLE using Lasso. The semi-supervised VNLE using SD and Lasso also demonstrates a line rate improvement >100% at the 4.5 × 10−3 Pre-FEC BER threshold over the conventional supervised VLNE using OLS.

BACKGROUND: Idiopathic mesenteric phlebosclerosis (IMP) is a rare disease, and its etiology and risk factors remain uncertain. AIM: To investigate the possible influence of Chinese herbal liquid containing geniposide on IMP. METHODS: The detailed formula of herbal liquid prescriptions of all patients was studied, and the herbal ingredients were compared to identify the toxic agent as a possible etiological factor. Abdominal computed tomography (CT) and colonoscopy images were reviewed to determine the extent and severity of mesenteric phlebosclerosis and the presence of findings regarding colitis. The disease CT score was determined by the distribution of mesenteric vein calcification and colon wall thickening on CT images. The drinking index of medicinal liquor was calculated from the daily quantity and drinking years of Chinese medicinal liquor. Subsequently, Spearman's correlation analysis was conducted to evaluate the correlation between the drinking index and the CT disease score. RESULTS: The mean age of the 8 enrolled patients was 75.7 years and male predominance was found (all 8 patients were men). The patients had histories of 5-40 years of oral Chinese herbal liquids containing geniposide and exhibited typical imaging characteristics (e.g., threadlike calcifications along the colonic and mesenteric vessels or associated with a thickened colonic wall in CT images). Calcifications were confined to the right-side mesenteric vein in 6 of the 8 patients (75%) and involved the left-side mesenteric vein of 2 cases (25%) and the calcifications extended to the mesorectum in 1 of them. The thickening of colon wall mainly occurred in the right colon and the transverse colon. The median disease CT score was 4.88 (n = 7) and the median drinking index was 5680 (n = 7). After Spearman's correlation analysis, the median CT score of the disease showed a significant positive correlation with the median drinking index (r = 0.842, P < 0.05). CONCLUSION: Long-term oral intake of Chinese herbal liquid containing geniposide may play a role in the pathogenesis of IMP.

Tunable frequency response is designed and experimentally demonstrated in this paper. The performance of frequency response in proposed radio-over-fiber (RoF) systems is investigated in terms of theoretical analysis, simulations, and experimental results with various fiber transmission distances. The notch in frequency response can be easily circumvented by changing the oriented angle of polarized lightwave in the proposed direct detection (DD) scheme. For comparison, the conventional Mach-Zehnder modulator (MZM) based DD scheme suffers from fixed frequency notch at certain frequencies, which generates forbidden frequency bands for W-band signal delivery. Our experimental results show that the proposed DD scheme exhibits a stable EVM performance of the 16-QAM signal from 83 GHz to 87 GHz via 25-km standard single-mode fiber (SSMF) and 1-m wireless transmission. On the contrary, the conventional MZM-based DD scheme encounters severe signal degradation at 85 GHz and 86 GHz. In this paper, the proposed scheme is implemented to demonstrate full bandwidth availability within a desirable frequency range by tuning the frequency response. Furthermore, a 10-Gbps 16-QAM signal located at 85 GHz is successfully transmitted by the proposed DD scheme which can provide 10-gigabit data transmission under 5G requirement.