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Maternal exposure to antibiotics existing in the environment is a predisposing factor for developmental malformation with metabolic disorders in offspring. In this study, female zebrafish (3 months) were exposed to 0.05 mg/L and 0.5 mg/L florfenicol (FF) for 28 days. After pairing and spawning with healthy male fish, F1 embryos were collected and developed to 5 d post-fertilization (dpf) in clear water. And the adverse effects on the F1 generation were examined thoroughly. The fecundity of F0 female fish and the hatchability, mortality, and body length of F1 larvae significantly decreased in the treatment group. Meanwhile, multi-malformation types were found in the exposure group, including delayed yolk sac absorption, lack of swim bladder, and spinal curvature. Metabolomic and transcriptomic results revealed alterations in metabolism with dysregulation in tricarboxylase acid cycle, amino acid metabolism, and disordered lipid metabolism with elevated levels of glycerophospholipid and sphingolipid. Accompanying these metabolic derangements, decreased levels of ATP and disordered oxidative-redox state were observed. These results were consistent with the damaged mitochondrial membrane potential and respiratory chain function, suggesting that the developmental toxicity and perturbed metabolic signaling in the F1 generation were related to the mitochondrial injury after exposing F0 female zebrafish to FF. Our findings highlighted the potential toxicity of FF to offspring generations even though they were not directly exposed to environmental contaminants. • The adverse effect of maternal exposure to florfenicol on F1 larvae was studied. • Decreased hatchability and increased malformation rate were observed. • The level of metabolites, lipids, and related gene expression were changed. • Impaired mitochondrial and disordered cellular oxidative state were observed. [ABSTRACT FROM AUTHOR]

• An all-optical format conversion (AOFC) scheme from 4-ary pulse amplitude modulation (PAM4) to quadrature phase shift keying (QPSK) based on the non-degenerate phase-sensitive amplification (PSA) and the pump assisted nonlinear optical loop mirror (PA-NOLM) is proposed and numerically simulated for the first time. • The input unipolar PAM4 signal with equal amplitude distance (UPAM4-A) is coupled with two input pump lights and injected into the symmetric interferometric fiber optic parameter amplifier (FOPA) to achieve the separation of the UPAM4-A and the new pump light generated at the signal frequency based on the non-degenerate PSA. When the filtered out UPAM4-A is coherent added with the new generated pump, the UPAM4-A signal to the biplolar PAM4 (BPAM4) signal. When the converted BPAM4 is sent into the PA-NOLM after adjusting its power, the BPAM4 signal could be converted into the QPSK signal. • The error vector magnitude (EVM) and bit error ratio (BER) performance of the system are measured before and after AOFC with different input and receiver optical signal to noise ratio (OSNR). For the input UPAM4-A signal with an input OSNR of 27 dB, there is about 8.2 dB BER performance improvement in receiver OSNR for the final converted QPSK signal. • The proposed non-degenerate PSA configuration can be extended to realize the AOFC from one QPSK to two on–off keying (OOK) signals. The scheme can be applied in the optical gateway connecting the long-haul and the short-reach optical networks with suitable modulation formats. An all-optical format conversion (AOFC) scheme from 4-ary pulse amplitude modulation (PAM4) to quadrature phase shift keying (QPSK) based on the non-degenerate phase-sensitive amplification (PSA) and the pump assisted nonlinear optical loop mirror (PA-NOLM) is proposed and numerically simulated for the first time. The input unipolar PAM4 signal with equal amplitude distance (UPAM4-A) is coupled with two input pump lights and injected into the symmetric interferometric fiber optic parameter amplifier (FOPA) to achieve the separation of the UPAM4-A and the new pump light generated at the signal frequency based on the non-degenerate PSA. When the filtered out UPAM4-A is coherent added with the new generated pump, the UPAM4-A signal to the biplolar PAM4 (BPAM4) signal. When the converted BPAM4 is sent into the PA-NOLM after adjusting its power, the BPAM4 signal could be converted into the QPSK signal. The error vector magnitude (EVM) and bit error ratio (BER) performance of the system are measured before and after AOFC with different input and receiver optical signal to noise ratio (OSNR). For the input UPAM4-A signal with an input OSNR of 27 dB, there is about 8.2 dB BER performance improvement in receiver OSNR for the final converted QPSK signal. Additionally, the proposed non-degenerate PSA configuration can be extended to realize the AOFC from one QPSK to two on–off keying (OOK) signals. The scheme can be applied in the optical gateway connecting the long-haul and the short-reach optical networks with suitable modulation formats. [ABSTRACT FROM AUTHOR]

The current study investigates carbon neutrality targets for the US's case while analyzing the role of environmental-related research and development (ERR&D) and renewable energy research and development (RER&D). This study also considered economic growth (GDP) and energy productivity (EP) as controlled variables. Utilizing the time series data over the period from 1990 to 2019, this study used various econometric approaches, such as unit root tests and cointegration tests for stationarity and the long-run association between variables, respectively. This study's main econometric regression tools, such as dynamic ordinary least square (DOLS) and fully modified ordinary least square (FMOLS), are utilized. The empirical findings reveal that economic growth played a negative role in achieving carbon neutrality targets. However, EP, RER&D, and ERR&D positively contribute to carbon neutrality target achievement by reducing atmospheric CO 2 emissions. Moreover, this study found a cointegration relationship between the study variables. The bidirectional causality is found between ERR&D and CO 2 emissions, while a unidirectional causality is observed, running from exogenous variables towards CO 2 emissions. Based on the empirical findings, this study recommends expanding the investment and expenditures in both ERR&D and RER&D sectors to attain carbon neutrality. • The current study investigates carbon neutrality targets for the US's case. • The study analyses environment-related research and development (ERR&D). • The study used advanced econometric methods for analysis. • The results show ERR&D positively contributes to the carbon neutrality target. • The bidirectional causality is found between ERR&D and CO 2 emissions. [ABSTRACT FROM AUTHOR]

An all-optical wavelength and format conversion scheme of 20 Gbps differential quadrature phase shift keying (DQPSK)-to-4-ary pulse amplitude modulation (PAM4) signals based on the delay line interferometer (DLI) and the pump assisted nonlinear optical loop mirror (NOLM) is proposed and numerically simulated. The input DQPSK signal is converted into two star-16-ary quadrature amplitude modulation (star-16QAM) signals (namely, star-16QAM-I and star-16QAM-Q) using DLI with the time delay of 1-symbol and different linear phase shifts of π / 4 and − π / 4 , respectively. The star-16QAM signals are converted into the on-off keying (OOK) signals (namely, OOK-I and OOK-Q) using the pump assisted NOLM based on the self-phase modulation (SPM) and the cross-phase modulation (XPM) in the highly nonlinear fiber (HNLF). The two OOK signals can be aggregated into different types of PAM4 signals by adjusting their power ratio (PR) and relative phase shift (RPS) flexibly. Error vector magnitude (EVM) and bit error rate (BER) for the input and output optical signals are calculated to verify the scheme performance. Compared to the DQPSK signal with an input optical signal-to-noise ratio (OSNR) of 30 dB, there are about 2.5 dB penalty of receiver OSNR for the converted OOK-I and OOK-Q signals. For the corresponding aggregated equidistant PAM4 and equiamplitude PAM4 signals, they have about 6.3 dB and 12.1 dB penalty of receiver OSNR. The proposed scheme of DQPSK-to-PAM4 can be deployed at the all-optical gateway to bridge the long-hual and short-reach optical networks. • An all-optical wavelength and format conversion scheme of 20 Gbps differential quadrature phase shift keying (DQPSK)-to-4-ary pulse amplitude modulation (PAM4) signals based on the delay line interferometer (DLI) and the pump assisted nonlinear optical loop mirror (NOLM) is proposed and numerically simulated. • The input DQPSK signal is converted into two star-16QAM signals using DLI with the time delay of 1-symbol and different linear phase shifts of π /4 and − π /4, respectively. The star-16QAM signals are converted into two OOK signals using the pump assisted NOLM based on the SPM and XPM in the HNLF. When the power ratio (PR) and relative phase shift (RPS) between the two OOK signals are adjusted flexibly, different types of PAM4 signals can be aggregated by vector superposition. • The proposed scheme of DQPSK-to-PAM4 can be deployed at the all-optical gateway to bridge the long-hual and short-reach optical networks. [ABSTRACT FROM AUTHOR]

An all-optical aggregation and de-aggregation scheme between on–off keying (OOK) signals, quadrature phase shift keying (QPSK) signals and 8-ary quadrature amplitude modulation (8QAM) signals is proposed and numerically simulated based on nonlinear effects in the high nonlinear fiber (HNLF). In the de-aggregation processing, the input 30 Gbit/s 8QAM signal is firstly de-aggregated into one 20 Gbit/s QPSK signal and one 10 Gbit/s binary phase shift keying (BPSK) signal by deploying self-phase modulation (SPM), cross-phase modulation (XPM), four-wave mixing (FWM) and parameter amplification (PA) effects. One continuous optical carrier can be extracted from the converted BPSK signal by designing a feed-forward based modulation stripping configuration. The converted OOK signal can be obtained through vector superposition between the extracted optical carrier and the converted BPSK signal. In the aggregation processing, the converted 20 Gbit/s QPSK signal and the 10 Gbit/s OOK signal are fed to another HNLF and aggregated into one 30 Gbit/s 8QAM signal again by utilizing XPM and PA effects. Moreover, the aggregated 8QAM signal keeps the same wavelength and information integrity as the input 8QAM signal. the Error vector magnitude (EVM) and the bit error ratio (BER) for the 8QAM signal before and after aggregation and de-aggregation are measured to evaluate the scheme performance. The proposed all-optical aggregation and de-aggregation scheme for the advanced and simple modulation formats can be applied at the intermediate network node (INN) to solve the network traffic aggregation and de-aggregation with different modulation formats. • An all-optical format conversion scheme is proposed between 8QAM and QPSK, OOK signals using nonlinear effects in high nonlinear fiber. • 8QAM is converted into QPSK through amplitude saturation and SPM effects. XPM and PA are used to convert 8QAM into BPSK. • One optical carrier is extracted from the converted BPSK signal. • The converted OOK signal is obtained through vector superposition between the extracted optical carrier and converted BPSK signal. • The converted QPSK and OOK can be aggregated into 8QAM by XPM and PA. The scheme is suit for the future dynamically re-configurable optical networks at the gateways. [ABSTRACT FROM AUTHOR]

The generation of nonclassical multiphoton has aroused and renewed interest in recent years. Here, we theoretically propose a new method to generate a temporal triplet correlation via a spontaneous six-wave mixing process. In the dressed-state picture at atomic ensemble, we forecast two or more different resonant dispersion modes of each generated photons. With energy conservation condition, these resonant dispersion modes compose multiple six-wave mixing processes, and the different processes could beat with each other. When we only consider the nonlinear optical response, the coincidence counts of triplets perform as a damped Rabi oscillation (three conditional two-photon correlations with four or six periods) because of the destructive interference among the possible six-wave mixing processes. The coherent time in the system is determined by the effective dephasing rate. Furthermore, we study the triphoton correlation with the fifth-order nonlinear susceptibility and the phase matchings mixing. • New method of generating triplet correlation via a single six-wave mixing process. • Frequency modes cause multiple six-wave mixing processes beating with each other. • Damped Rabi oscillation from destructive interference of six-wave mixing processes. • The mixture of the fifth-order nonlinear susceptibility and the phase matchings. [ABSTRACT FROM AUTHOR]