Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre

Mode division multiplexing (MDM)– using a multimode optical fiber’s N spatial modes as data channels to transmit N independent data streams – has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting’s 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than −15 dB mode selectivity and without cascaded beam splitting’s 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM−1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10−3

CURVE SPRINTING KINEMATICS EXHIBITED BY ATHLETES USING A SINGLE, TRANS-TIBIAL PROSTHESIS

The purpose of our study was to determine whether kinematics exhibited during the curve section of a 200 m sprint are influenced by ‘limb type’ (prosthetic vs nonprosthetic limb) or ‘prosthetic limb side’ (‘inside’ compared to the ‘outside’ of the curve). Two video cameras (60 Hz) were used to capture 13 male athletes using a single, trans-tibial prosthesis during an international, 200 m T-44 competition. From mixed-model ANOVA (p < .05), prosthetic and nonprosthetic limb kinematics were different, but differences were dependent on the prosthetic limb side. The inside versus outside prosthetic limb may be affected more due to the rotational influences that affect the inside and outside foot differently. Therefore, athletes whose prosthetic limb was on the inside may be at a disadvantage compared to those with an outside prosthetic limb

Provably Secure and Practical Quantum Key Distribution over 307 km of Optical Fibre

Proposed in 1984, quantum key distribution (QKD) allows two users to exchange provably secure keys via a potentially insecure quantum channel. Since then, QKD has attracted much attention and significant progress has been made in both theory and practice. On the application front, however, the operating distance of practical fibre-based QKD systems is limited to about 150 km, which is mainly due to the high background noise produced by commonly used semiconductor single-photon detectors (SPDs) and the stringent demand on the minimum classical- post-processing (CPP) block size. Here, we present a compact and autonomous QKD system that is capable of distributing provably-secure cryptographic key over 307 km of ultra-low-loss optical fibre (51.9 dB loss). The system is based on a recently developed standard semiconductor (inGaAs) SPDs with record low background noise and a novel efficient finite-key security analysis for QKD. This demonstrates the feasibility of practical long-distance QKD based on standard fibre optic telecom components.Comment: 6+7 pages, 3 figure

Relations of current and past cancer with severe outcomes among 104,590 hospitalized COVID-19 patients: The COVID EHR cohort at the University of Wisconsin

BACKGROUND: There is mixed evidence about the relations of current versus past cancer with severe COVID-19 outcomes and how they vary by patient and cancer characteristics. METHODS: Electronic health record data of 104,590 adult hospitalized patients with COVID-19 were obtained from 21 United States health systems from February 2020 through September 2021. In-hospital mortality and ICU admission were predicted from current and past cancer diagnoses. Moderation by patient characteristics, vaccination status, cancer type, and year of the pandemic was examined. RESULTS: 6.8% of the patients had current (n = 7,141) and 6.5% had past (n = 6,749) cancer diagnoses. Current cancer predicted both severe outcomes but past cancer did not; adjusted odds ratios (aOR) for mortality were 1.58 [95% confidence interval (CI), 1.46-1.70] and 1.04 (95% CI, 0.96-1.13), respectively. Mortality rates decreased over the pandemic but the incremental risk of current cancer persisted, with the increment being larger among younger vs. older patients. Prior COVID-19 vaccination reduced mortality generally and among those with current cancer (aOR, 0.69; 95% CI, 0.53-0.90). CONCLUSIONS: Current cancer, especially among younger patients, posed a substantially increased risk for death and ICU admission among patients with COVID-19; prior COVID-19 vaccination mitigated the risk associated with current cancer. Past history of cancer was not associated with higher risks for severe COVID-19 outcomes for most cancer types. IMPACT: This study clarifies the characteristics that modify the risk associated with cancer on severe COVID-19 outcomes across the first 20 months of the COVID-19 pandemic. See related commentary by Egan et al., p. 3

Complete Genome Sequence of the Avian Pathogenic Escherichia coli Strain APEC O78

Colibacillosis, caused by avian pathogenic Escherichia coli (APEC), is a significant disease, causing extensive animal and financial losses globally. Because of the significance of this disease, more knowledge is needed regarding APEC\u27s mechanisms of virulence. Here, we present the fully closed genome sequence of a typical avian pathogenic E. coli strain belonging to the serogroup O78

tkt1, located on a novel pathogenicity island, is prevalent in avian and human extraintestinal pathogenic Escherichia coli

<p>Abstract</p> <p>Background</p> <p>Extraintestinal pathogenic <it>Escherichia coli </it>are important pathogens of human and animal hosts. Some human and avian extraintestinal pathogenic <it>E. coli </it>are indistinguishable on the basis of diseases caused, multilocus sequence and phylogenetic typing, carriage of large virulence plasmids and traits known to be associated with extraintestinal pathogenic <it>E. coli </it>virulence.</p> <p>Results</p> <p>The gene <it>tkt1 </it>identified by a previous signature-tagged transposon mutagenesis study, was found on a 16-kb genomic island of avian pathogenic <it>Escherichia coli </it>(APEC) O1, the first pathogenic <it>Escherichia coli </it>strain whose genome has been completely sequenced. <it>tkt1 </it>was present in 39.6% (38/96) of pathogenic <it>Escherichia coli </it>strains, while only 6.25% (3/48) of <it>E. coli </it>from the feces of apparently healthy chickens was positive. Further, <it>tkt1 </it>was predominantly present in extraintestinal pathogenic <it>E. coli </it>belonging to the B2 phylogenetic group, as compared to extraintestinal pathogenic <it>E. coli </it>of other phylogenetic groups. The <it>tkt1</it>-containing genomic island is inserted between the <it>metE </it>and <it>ysgA </it>genes of the <it>E. coli </it>K12 genome. Among different extraintestinal pathogenic <it>E. coli </it>of the B2 phylogenetic group, 61.7% of pathogenic <it>Escherichia coli</it>, 80.6% of human uropathogenic <it>E.coli </it>and 94.1% of human neonatal meningitis-causing <it>E. coli</it>, respectively, harbor a complete copy of this island; whereas, only a few avian fecal <it>E. coli </it>strains contained the complete island. Functional analysis showed that Tkt1 confers very little transketolase activity but is involved in peptide nitrogen metabolism.</p> <p>Conclusion</p> <p>These results suggest <it>tkt1 </it>and its corresponding genomic island are frequently associated with avian and human ExPEC and are involved in bipeptide metabolism.</p