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The future Internet is very likely the mixture of all-optical Internet with low power consumption and quantum Internet with absolute security guaranteed by the laws of quantum mechanics. Photons would be used for processing, routing and com-munication of data, and photonic transistor using a weak light to control a strong light is the core component as an optical analogue to the electronic transistor that forms the basis of modern electronics. In sharp contrast to previous all-optical tran-sistors which are all based on optical nonlinearities, here I introduce a novel design for a high-gain and high-speed (up to terahertz) photonic transistor and its counterpart in the quantum limit, i.e., single-photon transistor based on a linear optical effect: giant Faraday rotation induced by a single electronic spin in a single-sided optical microcavity. A single-photon or classical optical pulse as the gate sets the spin state via projective measurement and controls the polarization of a strong light to open/block the photonic channel. Due to the duality as quantum gate for quantum information processing and transistor for optical information processing, this versatile spin-cavity quantum transistor provides a solid-state platform ideal for all-optical networks and quantum networks. [ABSTRACT FROM AUTHOR]

The realization of quantum computers and quantum Internet requires not only quantum gates and quantum memories, but also transistors at single-photon levels to control the flow of information encoded on single photons. Single-photon transistor (SPT) is an optical transistor in the quantum limit, which uses a single photon to open or block a photonic channel. In sharp contrast to all previous SPT proposals which are based on single-photon nonlinearities, here I present a design for a high-gain and high-speed (up to THz) SPT based on a linear optical effect: giant circular birefringence induced by a single spin in a double-sided optical microcavity. A gate photon sets the spin state via projective measurement and controls the light propagation in the optical channel. This spin-cavity transistor can be directly configured as diodes, routers, DRAM units, switches, modulators, etc. Due to the duality as quantum gate and transistor, the spin-cavity unit provides a solid-state platform ideal for future Internet: a mixture of all-optical Internet with quantum Internet. [ABSTRACT FROM AUTHOR]

Giant optical Faraday rotation (GFR) and giant optical circular birefringence (GCB) induced by a single quantum-dot spin in an optical microcavity can be regarded as linear effects in the weak-excitation approximation if the input field lies in the low-power limit [Hu et al., Phys. Rev. B 78, 085307 (2008); Hu et al., Phys. Rev. B 80, 205326 (2009)]. In this work, we investigate the transition from the weak-excitation approximation moving into the saturation regime comparing a semiclassical approximation with the numerical results from a quantum optics toolbox [Tan, J. Opt. B 1, 424 (1999)]. We find that the GFR and GCB around the cavity resonance in the strong-coupling regime are input field independent at intermediate powers and can be well described by the semiclassical approximation. Those associated with the dressed state resonances in the strong-coupling regime or merging with the cavity resonance in the Purcell regime are sensitive to input field at intermediate powers, and cannot be well described by the semiclassical approximation due to the quantum-dot saturation. As the GFR and GCB around the cavity resonance are relatively immune to the saturation effects, the rapid readout of single-electron spins can be carried out with coherent state and other statistically fluctuating light fields. This also shows that high-speed quantum entangling gates, robust against input power variations, can be built exploiting these linear effects. [ABSTRACT FROM AUTHOR]

The effect of hydrology and land use on the sources and molecular composition of dissolved organic matter (DOM) within large rivers is vital for carbon cycling. However, it is still unclear how hydrological change influences the response of DOM composition to land use. Here, we report longitudinal patterns in DOM content and composition based on absorbance and fluorescence measurements along the middle Reaches of the Yangtze river, during two contrasting hydrological seasons. We found that soil leachate, metropolitan effluent, and microbiological production mainly contribute to the composition of DOM in the middle Yangtze. In addition, the relationship between land use and the fluorescence fingerprint of riverine DOM was season dependent. During the wet season, a higher content of aromatic and humic DOM was mobilized due to enhanced forest soil erosion, and relatively shallow soil-to-mainstem flow paths (R2 = 0.76, p < 0.01). While in the dry season, a higher content of aliphatic and protein-like DOM was likely derived from the deeper subsoil horizons or groundwater from the waters area (R2 = 0.54, p < 0.01), due to declined water level of the mainstem. Changes in water residence time modulate the fate of DOM in the Three Gorges Reservoir. Flocculation, adsorption and photochemical degradation promoted the removal of terrestrial organic substances in the wet season, while microbial activity was beneficial to autochthonous DOM production in the dry season. Overall, this study advances our evaluation of the effect of seasonal hydrological scenarios on the relationship between DOM and land use in large monsoonal river systems. [ABSTRACT FROM AUTHOR]

This study aimed to provide evidence of the associations between pre- and post-birth and adulthood air pollution exposure with telomere length. The databases of PubMed, Embase, and Web of Science were searched up to June 1st, 2022 in order to include relevant observational studies and perform a systematic review and meta-analysis. The random-effects meta-analysis was grouped by air pollutant and exposure window (pre- and post-birth and adulthood) to evaluate the summary effect estimate. Cochran's Q and I2 statistics were used to evaluate the heterogeneity among the included studies. The quality of individual studies was evaluated using the national toxicology program/office of health assessment and translation risk of bias rating tool. We identified 18 studies, covering 8506 children and 2263 adults from multiple countries. We found moderate evidence that particulate matter less than 2.5 μm (PM 2.5) exposure during the entire pregnancy (−0.043, 95% CI: −0.067, −0.018), nitrogen dioxide (NO 2) exposure during the first trimester (−0.016, 95% confidence interval [CI]: −0.027, −0.005), long-term adulthood PM 2.5 exposure were associated with shortening telomere length. Mild to high between-study heterogeneity was observed for the most tested air pollutant-telomere length combinations in different exposure windows. This systematic review and meta-analysis provides the evidence which strongly supports that prenatal PM 2.5 and NO 2 exposures were related to reduced telomere length, while prenatal sulfur dioxide (SO 2) and carbon monoxide (CO) exposures, childhood PM 2.5 , particulate matter less than 10 μm (PM 10), NO 2 exposures and short-term adulthood PM 2.5 and PM 10 exposures were not associated with telomere length. Further high-quality studies are needed to elaborate our suggestive associations. [ABSTRACT FROM AUTHOR]

We present the first study of Ca isotope cycling in a natural cave system, with measurements of bedrock, dripwater and recently formed carbonate, coupled to a first stalagmite time-series spanning the 8.2 kyr event. Dripwaters at Heshang Cave (Central China; 30°27′N, 110°25′E) are isotopically heavy relative to the dolomite bedrock, the result of prior calcite precipitation (PCP) occurring earlier in the drip flow path. A simple Rayleigh fractionation model quantifies the extent of PCP in the modern environment at 36% Ca removal. The observed in situ calcium isotope fractionation factor between dripwater and carbonate is Δ 44 / 42 Ca = − 0.63 ± 0.03 ‰ and does not vary during the annual cycle. Measurements of speleothem carbonate spanning the 8.2 kyr event show the response of Ca isotopes to changing climate. δ 44/42 Ca increases by 0.35‰ at the onset of the event, coeval with changes in δ 18 O and Mg/Ca, and remains high for 80 yr. This change is explained by decreased rainfall leading to increased PCP; an interpretation supported by established PCP proxies (Mg/Ca, Sr/Ca and Ba/Ca). Ca isotopes indicate that PCP increased to 60% Ca removal during the event, which, from application of a simple box model, suggests mean annual rainfall decreased by approximately a third in Central China during the 8.2 kyr event. The response of Ca isotopes across this event demonstrates their potential for the assessment of past conditions, including past dripwater flow rates and rainfall. [ABSTRACT FROM AUTHOR]

Background The practice of salvaging recurrent rectal cancer has evolved. The aim of this study was to define the evolving salvage potential over time among patients with locally recurrent disease, and to identify durable determinants of long-term success. Methods The study included consecutive patients with recurrent rectal cancer undergoing multimodal salvage with curative intent between 1988 and 2012. Predictors of long-term survival were defined by Cox regression analysis and compared over time. Re-recurrence and subsequent treatments were evaluated. Results After multidisciplinary evaluation of 229 patients, salvage therapy with curative intent included preoperative chemotherapy and/or radiotherapy (73·4 per cent; with 41·3 per cent undergoing repeat pelvic irradiation), surgical salvage resection with or without intraoperative irradiation (36·2 per cent), followed by postoperative adjuvant chemotherapy (38·0 per cent). Multivisceral resection was undertaken in 47·2 per cent and bone resection in 29·7 per cent. The R0 resection rate was 80·3 per cent. After a median follow-up of 56·5 months, the 5-year overall survival rate was 50 per cent in 2005-2012, markedly increased from 32 per cent in 1988-1996 ( P = 0·044). Long-term success was associated with R0 resection ( P = 0·017) and lack of secondary failure ( P = 0·003). Some 125 patients (54·6 per cent) developed further recurrence at a median of 19·4 months after salvage surgery. Repeat operative rescue was feasible in 21 of 48 patients with local re-recurrence alone and in 17 of 77 with distant re-recurrence, with a median survival of 19·8 months after further recurrence. Conclusion The long-term salvage potential for recurrent rectal cancer improved significantly over time, with the introduction of an individualized treatment algorithm of multimodal treatments and surgical salvage. Durable predictors of long-term success were R0 resection at salvage operation, avoidance of secondary failure, and feasibility of repeat rescue after re-recurrence. [ABSTRACT FROM AUTHOR]

As an important part of food safety, the safety of food packaging has received much attention from both the ordinary people and the government. Therefore the government has enhanced its supervision of the impact of packaging on the food safety. This paper reviews the laws, regulations and standards on safety of food packaging, and the migration investigation in China. Special focus is on the issues like the additives in food packaging and paper packaging. The advances in migration testing, migration model and molecular dynamics simulation on migration in China are enhanced. [ABSTRACT FROM AUTHOR]

Methylene blue (MB) is a cationic dyestuff, which is particularly resistant to biodegradation. The molecular sieved γ-MnO2 was used as an adsorbent/oxidant to remove the MB at room temperature and in visible light. The removal efficiency was mainly evaluated by X-ray diffractometer (XRD), UV- Vis spectrometer (UV-Vis), total organic carbon (TOC). The results revealed that the mechanisms of MB removal by γ-MnO2 are significantly influenced by the pH. In acidic conditions, hypsochromic effects (i.e. blue shifts of UV-Vis spectra) resulting from N-demethylation of the dimethylamino group in MB may occur concomitantly with oxidative degradation by γ-MnO2. However, the TOC in solution after γ-MnO2 treatment in acidic conditions did not show a dramatic decrease. At near neutral pH conditions, there was almost no UV-Vis absorption for the MB solution, however, only 50% TOC removal was observed. It indicated that MB was not only adsorbed onto γ-MnO2 but also partially oxidatively degraded to other organic compounds which were colourless for UV-Vis. [ABSTRACT FROM AUTHOR]

We perform high-resolution reflection spectroscopy of a quantum dot resonantly coupled to a pillar microcavity. We show the change in reflectivity as the quantum dot is tuned through the cavity resonance and measure the quantum-dot-induced phase shift using an ultrastable interferometer. The macroscopic phase shift we measure could be extended to the study of charged quantum dot pillar microcavity systems, where it could be exploited to realize a high-efficiency spin photon interface for hybrid quantum information schemes. [ABSTRACT FROM AUTHOR]

Background New CD36 mutations are constantly being identified, although no study has specifically targeted a Taiwanese population. CD36 deficiency can result in dyslipid state and slow clearance of chylomicron. This could be linked to more frequent lipemic donations. Study Design and Methods We used flow cytometric methods to study the CD36 deficiency in 640 regular volunteer platelet apheresis donors from Taipei blood centre. The coding exons of CD36 gene were sequenced in CD36-deficient individuals, and the allele frequencies of CD36 variants were determined in the larger population by mutation-specific PCR and oligonucleotide hybridization. Visual inspection of lipemic plasma was routinely performed on samples taken before commencement of apheresis. Individuals found to have lipemic plasma are deferred until next donation. We investigated the link between positive lipemic deferral record and low platelet CD36 expression status. Results We found four donors (0·6%) with type I CD36 deficiency (both platelets and monocytes CD36null) and six (1·0%) with type II CD36 deficiency (PLT: CD36null, monocyte: CD36low). Six CD36 genetic variants were identified, two of them were novel, all but one are found exclusively in CD36null and CD36low expressors. Subjects with CD36 genetic variants also displayed deficient or reduced CD36 on monocytes. Donors with null or low PLT CD36 expression were more likely to have a lipemic deferral record than control subjects with normal PLT CD36 expression (X2 = 27·36, odds ratio = 2·6, 95% conference interval: 1·8–3·8, P < 0·0001). Conclusion Through this study, we established a donor registry to supply CD36-negative platelets for patients in need. [ABSTRACT FROM AUTHOR]

Background Thymic stromal lymphopoietin ( TSLP), IL-25, and IL-33 system contribute to the initiation and development of Th2 responses. This study aimed to explore the involvement of TSLP, IL-25, IL-33, and their receptors in type 2 T-helper (Th) responses in chronic rhinosinusitis with nasal polyps ( CRSw NPs) and their cross-regulation in human nasal epithelial cells ( HNECs). Methods Immunohistochemistry, quantitative RT- PCR, ELISA, Bio-Plex assay, and flow cytometry were used to detect the expression of TSLP/common γ-like TSLP receptor ( TSLPR)/ IL-7 receptor α ( IL-7Rα), IL-25/ IL-17B receptor ( IL-17 RB), and IL-33/membrane-bound ST2 ( ST2L)/soluble ST2 ( sST2) in sinonasal mucosa and HNECs. HNECs cultured at an air-liquid interface were used to explore the expression in regulation of these cytokine systems. Results Compared with controls and noneosinophilic CRSw NP, the expression of TSLP/ TSLPR/ IL-7Rα and ST2L/ sST2 was significantly increased in eosinophilic CRSw NP, predominantly in epithelial cells. In contrast, the expression of IL-33 and IL-25/ IL-17 RB was enhanced in epithelial cells in both eosinophilic and noneosinophilic CRSw NP compared to controls. The expression of TSLP, TSLPR, and ST2L was positively correlated with symptom and computer tomography scan scores in eosinophilic CRSw NP and with Th2 cytokine expression in sinonasal mucosa. The expression of ST2L was correlated with TSLP and its receptor expression. TSLP could induce ST2L expression that promoted IL-33-induced TSLP expression in HNECs. In addition, TSLP/ TSLPR/ IL-7Rα and ST2L could be induced by Th2 cytokines, while IL-25/ IL-17 RB and IL-33 could be upregulated by Th1/Th17 cytokines, in HNECs. Conclusions The positive feedback loop between TSLP, IL-33 and their receptors, and Th2 cytokines may facilitate Th2-skewed inflammation in eosinophilic CRSw NP. [ABSTRACT FROM AUTHOR]

Background:Colorectal cancer (CRC) diagnoses and disease-specific survival (DSS) vary between ethnic groups in the United States. However, few studies have assessed differences among Asian subgroups.Methods:The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients with invasive CRC between 1988 and 2008. Differences in clinicopathologic features, and DSS rates were compared among Asian subgroups. The California Health Interview Survey was used to examine risk factors and screening patterns for CRC.Results:The study included 359 374 patients with 8.4% Asian. Patients in all Asian subgroups were younger (median: 68 years) at diagnosis than non-Hispanic white (NHW) patients (median: 72 years). Most Asian subgroups, except Hawaiians, had better DSS than NHW patients although Asian subgroups had more advanced disease than NHW. Indian/Pakistani patients had a higher 5-year DSS than other Asian subgroups. Obesity proportions were lower in Asian subgroups (<50.2%) than in NHW (59.8%). Vietnamese men and Korean women had the lowest proportions of CRC screening. Advance tumour stages were highly associated with worse DSS in each ethnicity group. High tumour grades were associated with worse DSS in NHW, Filipino, and Chinese. Older age at diagnosis was associated with worse DSS in most ethnicity groups except Hawaiian and Vietnamese.Conclusion:Disparities exist between Asians and NHW with CRC, and among various Asian subgroups. Differences in cancer clinicopathologic features, patients' behavioural habits, lifestyle, and screening patterns may explain some differences in CRC survival observed among ethnic groups. [ABSTRACT FROM AUTHOR]