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In this brief, Nyquist-rate current-steering digital-to-analog converters (DACs) applying the random multiple data-weighted averaging (RMDWA) technique and the [Q.sub.N] rotated walk switching scheme are proposed such that high spurious-free dynamic range (SFDR) and small maximum output error can be achieved without calibrations, which are area and power consuming. RMDWA suppresses the harmonics caused by element mismatches to gain high SFDR performance. Furthermore, [Q.sub.N] rotated walk can lower the maximum output error when RMDWA and [Q.sup.N] rotated walk are employed simultaneously. Because the benefits of both dynamic element matching technique and switching scheme are obtained by the proposed DAC structure, the proposed structure can deliver smaller maximum output errors than traditional randomization techniques even if a low-cost small-area DAC with poor matching property is adopted. Index Terms--Digital-to-analog converters (DACs), dynamic element matching (DEM), spurious-free dynamic range (SFDR), switching scheme.

BACKGROUND: Methylmercury (MeHg) may affect fetal growth; however, prior research often lacked assessment of mercury speciation, confounders, and interactions. OBJECTIVE: Our objective was to assess the relationship between MeHg and fetal growth as well as the potential for confounding or interaction of this relationship from speciated mercury, fatty acids, selenium, and sex. METHODS: This cross-sectional study includes 271 singletons born in Baltimore, Maryland, 2004-2005. Umbilical cord blood was analyzed for speciated mercury, serum omega-3 highly unsaturated fatty acids (n-3 HUFAs), and selenium. Multivariable linear regression models controlled for gestational age, birth weight, maternal age, parity, prepregnancy body mass index, smoking, hypertension, diabetes, selenium, n-3 HUFAs, and inorganic mercury (IHg). RESULTS: Geometric mean cord blood MeHg was 0.94 µg/L (95% CI: 0.84, 1.07). In adjusted models for ponderal index, βln(MeHg) = -0.045 (g/[cm.sup.3]) X 100 (95% CI: -0.084, -0.005). There was no evidence of a MeHg X sex interaction with ponderal index. Contrastingly, there was evidence of a MeHg X n-3 HUFAs interaction with birth length [among low n-3 HUFAs, βpln(MeHg) = 0.40 cm, 95% CI: -0.02, 0.81; among high n-3 HUFAs, βpln(MeHg) = -0.15, 95% CI: -0.54, 0.25; p-interaction = 0.048] and head circumference [among low n-3 HUFAs, βpln(MeHg) = 0.01 cm, 95% CI: -0.27, 0.29; among high n-3 HUFAs, βpln(MeHg) = -0.37, 95% CI: -0.63, -0.10; p-interaction = 0.042]. The association of MeHg with birth weight and ponderal index was affected by n-3 HUFAs, selenium, and IHg. For birth weight, βpln(MeHg) without these variables was -16.8 g (95% CI: -75.0, 41.3) versus -29.7 (95% CI: -93.9, 34.6) with all covariates. Corresponding values for ponderal index were -0.030 (g/[cm.sup.3]) X 100 (95% CI: -0.065, 0.005) and -0.045 (95% CI: -0.084, -0005). CONCLUSION: We observed an association of increased MeHg with decreased ponderal index. There is evidence for interaction between MeHg and n-3 HUFAs; infants with higher MeHg and n-3 HUFAs had lower birth length and head circumference. These results should be verified with additional studies. http://dx.doi.org/10.1289/ehp.1408596, Introduction Impaired fetal growth has been associated with neonatal morbidity and mortality (Ashworth 1998; Cheung et al. 2002). Additionally, the impact of fetal growth restriction has been shown to extend [...]

 According  to  mRnd  powerestimates[12],  we  had  adequate  power  (>  80%)  toidentify effect estimates beyond ± 0.025.  Because  of  thepalindromic  nature  and  intermediate  allelefrequency  (A/T,  0.499/0.501)  of  this  SNP,  itsambiguous  strand  hindered  further  harmonizationfor  the effect  allele.  Five  otherloci  (i.e.,  rs2178575,  rs804279,  rs9696009,rs1784692,  and  rs11225154)  were  associated  witholigomenorrhea  (P <  5à 10â 8). To assess the causal  effect  of  maternal  PCOS onoffspring  birth  weight,  we  performed  two-sampleMR  using  R  3.6.1  software  and  the  TwoSampleMRpackage[6]. [Extracted from the article]

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. [ABSTRACT FROM AUTHOR]