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Vaccination shows efficacy in protecting from COVID-19, but regime and dosing optimization is still ongoing. Here the authors show that BNT162b2, mRNA-1273, or their combination with ChAdOx1 induces similar antibody responses, and those receiving three doses of BNT162b2 induce neutralizing antibodies against the Omicron variant. Two COVID-19 mRNA (of BNT162b2, mRNA-1273) and two adenovirus vector vaccines (ChAdOx1 and Janssen) are licensed in Europe, but optimization of regime and dosing is still ongoing. Here we show in health care workers (n = 328) that two doses of BNT162b2, mRNA-1273, or a combination of ChAdOx1 adenovirus vector and mRNA vaccines administrated with a long 12-week dose interval induce equally high levels of anti-SARS-CoV-2 spike antibodies and neutralizing antibodies against D614 and Delta variant. By contrast, two doses of BNT162b2 with a short 3-week interval induce 2-3-fold lower titers of neutralizing antibodies than those from the 12-week interval, yet a third BNT162b2 or mRNA-1273 booster dose increases the antibody levels 4-fold compared to the levels after the second dose, as well as induces neutralizing antibody against Omicron BA.1 variant. Our data thus indicates that a third COVID-19 mRNA vaccine may induce cross-protective neutralizing antibodies against multiple variants.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has raised concern about increased transmissibility, infectivity, and immune evasion from a vaccine and infection-induced immune responses. Although COVID-19 mRNA vaccines have proven to be highly effective against severe COVID-19 disease, the decrease in vaccine efficacy against emerged Beta and Delta variants emphasizes the need for constant monitoring of new virus lineages and studies on the persistence of vaccine-induced neutralizing antibodies. To analyze the dynamics of COVID-19 mRNA vaccine-induced antibody responses, we followed 52 health care workers in Finland for 6 months after receiving two doses of BNT162b2 vaccine with a 3-week interval. We demonstrate that, although anti-S1 antibody levels decrease 2.3-fold compared to peak antibody levels, anti-SARS-CoV-2 antibodies persist for months after BNT162b2 vaccination. Variants D614G, Alpha, and Eta are neutralized by sera of 100% of vaccinees, whereas neutralization of Delta is 3.8-fold reduced and neutralization of Beta is 5.8-fold reduced compared to D614G. Despite this reduction, 85% of sera collected 6 months postvaccination neutralizes Delta variant. IMPORTANCE A decrease in vaccine efficacy against emerging SARS-CoV-2 variants has increased the importance of assessing the persistence of SARS-CoV-2 spike proteinspecific antibodies and neutralizing antibodies. Our data show that after 6 months post two doses of BNT162b2 vaccine, antibody levels decrease yet remain detectable and capable of neutralizing emerging variants. By monitoring the vaccine-induced antibody responses, vaccination strategies and administration of booster doses can be optimized.

Two COVID-19 mRNA and two adenovirus vector vaccines have been licensed in Europe and various vaccine combinations and dosing strategies have been exploited to maximize the immunity against COVID-19. Here, we show that among health care workers (n=328) two doses of BNT162b2, mRNA-1273, or ChAdOx1 as also a combination of an adenovirus vector and mRNA vaccines induces equally high levels of anti-SARS-CoV-2 spike antibodies and neutralizing antibodies against B.1 and B.1.617.2 when administrated with a long 12-week dose interval. Two doses of BNT162b2 with a short 3-week interval induce 2-3-fold lower titers of neutralizing antibodies compared to the long interval. Third mRNA vaccine dose for the short dose interval group increased the antibody levels 4-fold compared to the levels after the second dose. Importantly, sera from all three-times vaccinated neutralized B.1.1.529 (Omicron). The data indicates that a third COVID-19 mRNA vaccine dose efficiently induces cross-protective neutralizing antibodies against multiple variants.

As SARS-CoV-2 has been circulating for over a year, dozens of vaccine candidates are under development or in clinical use. The BNT162b2 mRNA COVID-19 vaccine induces spike protein-specific neutralizing antibodies associated with protective immunity. The emergence of the B.1.1.7 and B.1.351 variants has raised concerns of reduced vaccine efficacy and increased re-infection rates. Here we show, that after the second dose, the sera of BNT162b2-vaccinated health care workers (n = 180) effectively neutralize the SARS-CoV-2 variant with the D614G substitution and the B.1.1.7 variant, whereas the neutralization of the B.1.351 variant is five-fold reduced. Despite the reduction, 92% of the vaccinees have a neutralization titre of >20 for the B.1.351 variant indicating some protection. The vaccinees’ neutralization titres exceeded those of recovered non-hospitalized COVID-19 patients. Our work provides strong evidence that the second dose of the BNT162b2 vaccine induces efficient cross-neutralization of SARS-CoV-2 variants currently circulating in the world.

We present a 16-Gb/s transmitter composed of a stacked voltage-mode CMOS driver and periodic-loaded reverse biased pn junction Mach–Zehnder modulator. The transmitter shows 9-dB extinction ratio and 10.3-pJ/bit power consumption and operates with 1.3 μm light. Penalties as low as 0.5 dB were seen as compared to a 25-Gb/s LiNbO3 transmitter with both a monolithic metal–semiconductor–metal receiver and a reference receiver at 16-Gb/s operation. We also present an analytic expression for relative transmitter penalty (RTP), which allows one to quickly assess the system impact of design parameters such as peak-to-peak modulator drive voltage, modulator figure of merit, and transmitter extinction ratio to determine the circumstances under which a stacked CMOS cascode driver is desirable.

We demonstrate 4 × 4 and 8 × 8 switch fabrics in multistage topologies based on 2 × 2 Mach-Zehnder interferometer switching elements. These fabrics are integrated onto a single chip with digital CMOS logic, device drivers, thermo-optic phase tuners, and electro-optic phase modulators using IBM's 90 nm silicon integrated nanophotonics technology. We show that the various switch-and-driver systems are capable of delivering nanosecond-scale reconfiguration times, low crosstalk, compact footprints, low power dissipations, and broad spectral bandwidths. Moreover, we validate the dynamic reconfigurability of the switch fabric changing the state of the fabric using time slots with sub-100-ns durations. We further verify the integrity of high-speed data transfers under such dynamic operation. This chip-scale switching system technology may provide a compelling solution to replace some routing functionality currently implemented as bandwidth- and power-limited electronic switch chips in high-performance computing systems.

A manufacturable platform of CMOS, RF and opto-electronic devices fully PDK enabled to demonstrate a 4×25 Gb/s reference design is presented. With self-aligned fiber attach, this technology enables low-cost O-band data-com transceivers. In addition, this technology can offer enhanced performance and yield in hybrid-assembly for applications at 25 Gbaud and beyond.

A novel high-speed Mach-Zehnder modulator (MZM) fully integrated into a 90 nm CMOS process is presented. The MZM features 'double-pass' optical phase shifter segments, and the first use of integrated inductors in a 'velocity-matched' distributed-electrode configuration.

We present a linear push-pull driven silicon modulator fabricated in IBM’s CMOS9WG technology node. The Si modulator shows third order nonlinearity suppression 3 dB superior in comparison with a commercial lithium niobate modulator.

We present a 20 Gb/s monolithically integrated transmitter with stacked CMOS driver and periodic-loaded PN-junction Mach-Zehnder modulator (MZM) fabricated in IBM’s sub-100nm technology node. Transmitter extinction ratios of 10 dB at 20 Gb/s are demonstrated.

A silicon microring modulator with independent resonance and coupling tunability is monolithically integrated with a stacked CMOS driver. At 25Gbps, the OMA is -1.9dBm, the extinction ratio is 3.5dB, and the excess loss is 2.6dB.

A single-die monolithically integrated multichannel silicon nanophotonics receiver is fabricated in IBM 90nm CMOS Nanophotonics technology node. Electrical eye diagrams for 16 channels exhibit open eyes up to 20Gbps with a 127mW/channel power efficiency.

A monolithically-integrated germanium receiver is fabricated in the IBM's newly established 90nm CMOS-integrated nanophotonics technology node. Technology is promising for cost-effective 10Gbps to 28Gbps optical communications links operating within extended temperature range up to 95°C.

A sub-100nm technology that allows the monolithic integration of optical devices as features into a 90nm base high-performance logic technology node is demonstrated. The technology is promising for next generation optical communications for applications.

We demonstrate a 1×2 ring resonator switch and a 2×2 Mach Zehnder switch, monolithically integrated with digital CMOS drivers in IBM's proprietary 90-nm photonics-enabled CMOS process. Static and dynamic performance metrics are characterized.

A coupling-modulated microring in an add-drop configuration for DPSK that uses the jt phase-flip in a 2×2 Mach-Zehnder interferometer coupler for the modulation is proposed. The concept is demonstrated in silicon-on-insulator at 10 Gb/s.

We demonstrate in a single chip a complete multiport photonic switching system using IBM 90-nm photonics-enabled CMOS. The system includes CMOS logic, switch drivers, multistage 4×4 and 8×8 photonic switch fabrics, and thermo-optic phase tuners.

http://tartu.ester.ee/record=b2655974~S1*est

The first sub-100nm technology that allows the monolithic integration of optical modulators and germanium photodetectors as features into a current 90nm base highperformance logic technology node is demonstrated. The resulting 90nm CMOS-integrated Nano-Photonics technology node is optimized for analog functionality to yield power-efficient single-die multichannel wavelength-mulitplexed 25Gbps transceivers.

An ultra-compact 10-wavelength WDM echelle grating receiver is demonstrated with 250 Gbps data receiving capability on a footprint of 0.96 mm2. Less than 1 dB channel-to-channel sensitivity variation is obtained at 25 Gbps.

Koagulas-negativa stafylokocker (KNS) klassas som en viktig del av hudens normalflora. Vid skador på hudens barriär som en inläggning av centrala venkatetrar (CVK) innebär kan dock KNS få tillträde till normalt sterila lokaler där de kan orsaka infektion. Vid utodling av borttagna CVK från patienter resistensbestäms bara några enstaka kolonier vilket gör det lätt att missa förekomst av flera olika stafylokock-kloner. Syftet med studien var att undersöka hur ofta en eller flera olika KNS-kloner förekommer på CVK från patienter, samt om det förekommer gemensamma kloner av KNS på CVK från olika patienter. Kolonier från CVK prov analyserades med den biokemiska fingerprintingmetoden Phene Plate-system (PhP). Resultatet visade 37 stycken CVK prov innehållande en klon, 23 stycken prov där det fanns 2 separata kloner, samt 6 prov med 3 kloner. Jämförelsen av kolonier ur prov från olika patienter resulterade i kluster med många gemensamma PhP-typer. I de 3 största klustren fanns 31, 15, respektive 8 kolonier representerande olika patienter. Den betydande andelen polyklonala CVK prov leder till risken att missa en mer resistent klon vilket då kan få konsekvensen felaktig antibiotikabehandling av patient. Att många patientprov hade en gemensam KNS-klon tyder på spridning av speciellt virulenta stammar inom sjukhus.

We propose a coupling-modulated microring in an add-drop configuration for binary phase-shift keying (BPSK), where data is encoded as 0 and π radian phase-shifts on the optical carrier. The device uses the π radian phase-flip across the zero coupling point in a 2 × 2 Mach-Zehnder interferometer coupler to produce the modulation. The coupling-modulated microring combines the drive power reduction of resonant modulators with the digital phase response of Mach-Zehnder BPSK modulators. A proof-of-concept device was demonstrated in silicon-on-insulator, showing differential binary phase-shift keying operation at 5 and 10 Gb/s.