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The multi-mode vertical-cavity surface-emitting lasers (MM-VCSELs) with different photonic crystal (PhC) designs in core and cladding regions are compared for transmitting the complex formatted QAM-OFDM data over 100-m OM5 multi-mode fiber (MMF). Among the designs with using flat core/cladding (denoting as Coreflat/Cladflat) and/or PhC core/cladding (denoting as Corephc/Cladphc) for the MM-VCSEL, the Coreflat+Cladflat VCSEL with the highest threshold current and large emission aperture provides the highest differential quantum efficiency of 0.11 and output power of 2 mW, whereas the Coreflat+Cladphc2 VCSEL with two periods of cladding PhC reveals the lowest threshold current of 2 mA, the highest modulation bandwidth of 15 GHz, the lowest relative intensity noise peak of -126 dBc/Hz and background level of -143 dBc/Hz. After pre-compensation, the Coreflat+Cladphc2 VCSEL chip can achieve the highest OFDM bandwidth of 18 GHz for 72-Gbit/s transmission in the BtB case. With additionally adding 1 period of core PhC, the Corephc1+Cladphc2 VCSEL possesses a single-mode lasing spectrum to facilitate the suppression of modal dispersion after MMF propagation. Hence, the Corephc1+Cladphc2 VCSEL exhibits the same bit rate of 60 Gbit/s as compared to the Coreflat+Cladphc2 VCSEL after 100-m OM5-MMF. After improving the analog bandwidth for waveform synthesis, the data rate of Coreflat+Cladphc2 VCSEL can successfully deliver 76-Gbit/s and 72-Gbit/s single-band 16-QAM OFDM data streams for BtB and 100-m OM5 MMF conditions via the pre-leveling technology. To date, the ultimate raw data rate achieves 92-Gbit/s with employing the multi-band QAM-OFDM data format.

Beyond 100-Gbit/s/λ high-speed inter-data-center link composed by hybridly integrated electro-absorption modulator (EAM) and distributed feedback laser diodes (DFBLD)-based transmitter at 1306 nm, and received by a PIN-PD + TIA optical receiver is demonstrated to carry 104-Gbit/s pre-emphasized PAM-4 data for 2–10 km single mode fiber (SMF) propagation. The EAM + DFBLD transmitter offers an average power of −1.5 dBm, an excellent side mode suppression ratio of 53 dB, an on/off extinction ratio up to 10 dB, an analog bandwidth of 25 GHz, and a relative intensity noise of -137 dBc/Hz. The PIN-PD + TIA module exhibits 30-GHz receiving bandwidth. For on-off keying (OOK) format, the allowable data rates at 62 and 60/54 Gbit/s for BtB and 2-km/10-km SMF cases obtain receiving BER of 1.48 × 10−13 and 3.4 × 10−14/1.77 × 10−14 qualified for error-free telecommunication. Even at simulated inter-data center link, the receiving power sensitivity and power penalty at 54 Gbit/s can achieve −6.43/−6.26 dBm and 0.07/0.24 dB after 2-/10-km SMF propagation. To efficiently utilize the limited transmitter bandwidth, the directly encoded PAM-4 data transmission reveals qualified BER slightly enlarged from 1.4 × 10−4 to 2.3 × 10−4 when transferred from back-to-back to 2-km SMF transmission. Lengthening the distance to 10-km SMF degrades the maximal PAM-4 data rate to 50 GBaud with a received BER of 2.3 × 10−4 (less than KP4-FEC criterion). The 50 GBaud PAM-4 link provides receiving power penalty of 0.11/0.24 dB after 2-/10-km SMF propagation, which is attributed to the narrow-linewidth DFBLD responsible for extremely low RF fading effect under nearly zero dispersion condition. The transmitting frontend with amplitude/phase pre-emphasis function makes the receiving end compact and cost-effective, which exhibits the higher spectral usage efficiency of 4 bit/s/Hz and the better receiving sensitivity of −5.5 dBm at the lower power budget of 2.8 fJoule/bit than previous works.

Hypoplastic left heart syndrome (HLHS) is a rare, but exceptionally serious, congenital heart defect. We aimed to explore the best-fitted Z-score models for individual chamber dimension and to draw a comparison between fetuses with HLHS and the normal Chinese cohort. We made measurements of 1674 healthy fetuses and 79 fetuses with HLHS, undertaking echocardiography. Normal fetal cardiovascular Z-score formulae were established by curve-fitting with 5 algorithmic functions and weighted regression of absolute residuals. Classic linear models were fitted for left ventricular diameter against gestational age, and log-transformed linear-power models-were statistically better for left ventricular length, diameter of left atrium and ascending aorta. Fetuses with HLHS manifested significantly lower Z-score means (≤3.5) for these 4 parameters and the vast majority (∼90%) lay beyond -2. Overall, cardiovascular Z-score equations were reliably constructed in a larger Chinese cohort, and their application should benefit evaluation and diagnosis of HLHS.

The underlying mechanisms of macrophage polarization have been detected by genome-wide transcriptome analysis in a variety of mammals. However, the transcriptome profile of rat genes in bone marrow-derived macrophages (BMM) at different activation statuses has not been reported. Therefore, we performed RNA-Sequencing to identify gene expression signatures of rat BMM polarized in vitro with different stimuli. The differentially expressed genes (DEGs) among unactivated (M0), classically activated pro-inflammatory (M1), and alternatively activated anti-inflammatory macrophages (M2) were analyzed by using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. In this study, not only we have identified the changes of global gene expression in rat M0, M1 and M2, but we have also made clear systematically the key genes and signaling pathways in the differentiation process of M0 to M1 and M2. These will provide a foundation for future researches of macrophage polarization.

Facial age is an important soft biometric trait for better identification of a human subject. The development of a facial age estimation system requires a large collection of age-labeled data. However, the imbalanced data distribution across age poses a major challenge to making a decent model to describe the variation of facial appearance caused by age. The cross-age data imbalance can be observed in common facial age datasets, for example, the MORPH [8], FG-NET [7] and the MIVIA dataset [3] considered in the GTA Contest. It can be often seen that insufficient data are provided for younger ages and senior ages, and the insufficiency becomes worsened as the age moves close to both ends. To deal with the data imbalance issues, many approaches implement various data augmentation schemes. In our approach, we propose a data augmentation scheme built upon the Age-Style GAN (ASGAN), which we propose for facial age regression and progression. In addition to the ASGAN-based data augmentation, we leverage the mean-variance loss to improve the age classification accuracy, and exploit face alignment as an auxiliary scheme to augment the whole dataset with an aligned subset. We conducted extensive experiments on the MIVIA dataset for verifying the performance of our approach.

Recently, biosensors have become widely deployed in consumer wearable devices, e.g., smart watches and wrist bands, to track user health conditions during sport, sleep, and daily activity. However, unlike biosignal acquisition in well-controlled medical settings, signal acquisition in consumer devices inevitably suffers from degraded signal quality due to poor sensor interfaces, motion artifacts, and environmental interferences, such as ambient light and power-line coupling, which can be >60dB stronger than the wanted signals. These challenges result in demanding AFE specifications, even under tight constraints on sensor area, chip size, and battery capacity, which are all necessary for wearable devices. This paper presents a multimodal biosensing SoC that addresses these issues to enable reliable Photoplethysmography (PPG), Electrocardiography (ECG), and Bio-impedance (BIOZ) acquisition under highly variable conditions in wearable devices. It contains a 130dB-DR PPG readout, which is 11dB higher than the state of the art [1], to tolerate strong ambient light; an ECG AFE with a pseudo Right-Leg-Drive (RLD) tolerant of >130V PP common-mode interference (CMI) from power-line coupling, which is 3× higher than the technique presented in [2]; and a BIOZ AFE for body-fat measurement using 1cm2 electrodes rather than the typically >10cm2 electrodes in conventional body-fat meters. The area for the entire PPG/ECG/BIOZ AFE is ~3mm2, which is around 50% smaller than prior AFEs with similar features [3], [4].

Recently, GaN-based light-emitting diodes (LEDs) find their applications in, other than general lighting, visible light communication (VLC) for high-speed wireless data networks. The pursuit for more bandwidth from the LED can be realized by engineering the LED material structure and device design, or by modulation techniques. In this paper, we proposed GaN-based LEDs with the photonic crystal (PhC) structure for VLC applications. Contradictory to general thought that higher small frequency response translates to better large-signal performance, our results reveal that a PhC LED may not perform well at low data rate due to its relatively poorer signal-to-noise ratio (SNR). However, at higher data rates, the performance of PhC LEDs surpasses conventional LED structure. We showed data transmission capability of PhC LEDs with a bit rate up to 400 Mb/s using on–off keying modulation. To demonstrate the chip capability for large-signal transmission, without using preemphasis or postemphasis, VLC with 16-quadrature amplitude modulation orthogonal frequency-division multiplexing transmission capacity up to 2 Gbit/s is achieved with an error vector magnitude of 17.07%, SNR of 15.35 dB, and bit error rate of $3.3 \times {10}^{-3}$ . Our LEDs embedded with PhCs pass the forward error correction criterion. The results reveal the advantages of LEDs with PhC for achieving higher data rate transmission.

Fatty acids are among the most studied nutrients in human metabolism and health. Endogenous fatty acid status influences health and disease via multiple mechanisms at all stages of the life cycle. Despite widespread interest, attempts to summarize the results of multiple studies addressing similar fatty acid–related outcomes via meta-analyses and systematic reviews have been disappointing, largely because of heterogeneity in study design, sampling, and laboratory and data analyses. Our purpose is to recommend best practices for fatty acid clinical nutrition and medical studies. Key issues in study design include judicious choice of sampled endogenous pools for fatty acid analysis, considering relevant physiologic state, duration of intervention and/or observation, consideration of specific fatty acid dynamics to link intake and endogenous concentrations, and interpretation of results with respect to known fatty acid ranges. Key laboratory considerations include proper sample storage, use of sample preparation methods known to be fit-for-purpose via published validation studies, detailed reporting or methods to establish proper fatty acid identification, and quantitative analysis, including calibration of differential response, quality control procedures, and reporting of data on a minimal set of fatty acids to enable comprehensive interpretation. We present a checklist of recommendations for fatty acid best practices to facilitate design, review, and evaluation of studies with the intention of improving study reproducibility.

Hexokinase-3 (HK3) is a member of hexokinase family, which can catalyze the first step of glucose metabolism. It can increase ATP levels, reduce the production of reactive oxygen species, increase mitochondrial biogenesis, protect mitochondrial membrane potential and play an antioxidant role. However, the change of its expression in spinal cord after injury is still unknown. In this study, we investigated the spatio-temporal expression of HK3 in the spinal cords by using a spinal cord injury (SCI) model in adult female Sprague-Dawley rats. Quantitative reverse transcription-PCR and western blot analysis revealed that HK3 could be detected in sham-opened spinal cords. After SCI, it gradually increased, reached a peak at 7 days post-injury (dpi), and then gradually decreased with the prolonging of injury time, but still maintained at a higher level for up to 28 dpi (the longest time evaluated in this study). Immunofluorescence staining showed that HK3 was found in GFAP+, β-tubulin III+ and IBA-1+ cells in sham-opened spinal cords. After SCI, in addition to the above-mentioned cells, it could also be found in CD45+ and CD68+ cells. These results demonstrate that HK3 is mainly expressed in astrocytes, neurons and microglia in normal spinal cords, and could rapidly increase in infiltrated leukocytes, activated microglia/macrophages and astrocytes after SCI. These data suggest that HK3 may be involved in the pathologic process of SCI by promoting glucose metabolism.