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To achieve the longest distance of 800 Gb/s unrepeatered transmission, we use commercial 800 Gb/s transceivers with soft-decision FEC, optimized high-order Raman pumps, and enhanced bidirectional ROPA with third-order Raman pumping in this experiment to optimize system performance. Two types of G.654E fibers are also fully characterized and used as span fibers. The improvement of transmission distance is mainly due to the remote pump power for RGU can be increased by nearly 4 dB in G.654E fiber by the third-order Raman pumping. At last, a single 800 Gb/s channel is transmitted over 447.96 km with a span loss of 73.16 dB. As far as we know, this is the longest 800 Gb/s unrepeatered transmission distance ever reported.

We present a multi-mode diode-pumped Yb:CALGO laser oscillator based on cross-polarization pumping. Using this method, we demonstrate 22-fs pulses at 0.3 W, which is the shortest duration for any Yb- based bulk laser oscillator utilizing multimode-diode pumping.

\"The over-exploitation of groundwater and marked changes in climate over recent decades has led to unacceptable declines in groundwater resources. Laboratory Manual for Groundwater, Wells, and Pumps serves as a valuable resource and provides a multi-disciplinary overview for academics, administrators, scientists, policymakers, and professionals involved in the managing sustainable groundwater development programs. It includes practical guidance on the measurement of groundwater flow, soil properties, aquifer properties, wells and their design, as well as the latest state-of-the-art information on pumps and their testing, and groundwater modeling\"-- Provided by publisher.

BackgroundRecent trends on outcomes in cardiogenic shock (CS) complicating acute myocardial infarction (AMI) suggest improvements in early survival. However, with the ever-changing landscape in management of CS, we sought to identify age-based trends in these outcomes and mechanical circulatory support (MCS) use among patients with both AMI and non-AMI associated shock.MethodsWe queried the 2005–2014 Nationwide Inpatient Sample databases to identify patients with a diagnosis of cardiogenic shock. Trends in the incidence of hospital-mortality, and use of MCS such as intra-aortic balloon pump (IABP), Impella/TandemHeart (IMP), and extra corporeal membrane oxygenation (ECMO) were analyzed within the overall population and among different age-categories (50 and under, 51–65, 66–80 and 81–99 years). We also made comparisons between patient groups admitted with CS complicating AMI and those with non-AMI associated CS.ResultsWe studied 144,254 cases of CS, of which 55.4% cases were associated with an AMI. Between 2005 and 2014, an overall decline in IABP use (29.8–17.7%; ptrend < 0.01), and an uptrend in IMP use (0.1–2.6%; ptrend < 0.01), ECMO use (0.3–1.8%; ptrend < 0.01) and in-hospital mortality (44.1–52.5% AMI related, 49.6–53.5% non-AMI related; ptrend < 0.01) was seen. Patients aged 81–99 years had the lowest rate of MCS use (14.8%), whereas those aged 51–65 years had highest rate of MCS use (32.3%). Multivariable analysis revealed that patients aged 51-65 years (aOR 1.46, 95% CI 1.40–1.52; p<0.001), 66–80 years (aOR 2.51, 95% CI 2.39–2.63; p<0.01) and 81–99 years (aOR 5.04, 95% CI 4.78–5.32; p<0.01) had significantly higher hospital mortality compared to patients aged ≤ 50 years. Patients admitted with CS complicating AMI were older and had more comorbidities, but lower hospital mortality (45.0 vs. 48.2%; p < 0.001) when compared to non-AMI related CS. We also noted that the proportion of patients admitted with CS complicating AMI significantly decreased from 2005 to 2014 (65.3–45.6%; ptrend < 0.01) whereas those admitted without an associated AMI increased.ConclusionsIABP use has declined whereas IMP and ECMO use has increased over time among CS admissions. Older age was associated with an incrementally higher independent risk for hospital mortality. Recent trends indicate an increase in both proportion of patients admitted with CS without associated AMI and in-hospital mortality across all CS admissions irrespective of AMI status.

In current international guidelines the recommendation for intra-aortic balloon pump (IABP) use has been downgraded in cardiogenic shock complicating acute myocardial infarction on the basis of registry data. In the largest randomised trial (IABP-SHOCK II), IABP support did not reduce 30 day mortality compared with control. However, previous trials in cardiogenic shock showed a mortality benefit only at extended follow-up. The present analysis therefore reports 6 and 12 month results. The IABP-SHOCK II trial was a randomised, open-label, multicentre trial. Patients with cardiogenic shock complicating acute myocardial infarction who were undergoing early revascularisation and optimum medical therapy were randomly assigned (1:1) to IABP versus control via a central web-based system. The primary efficacy endpoint was 30 day all-cause mortality, but 6 and 12 month follow-up was done in addition to quality-of-life assessment for all survivors with the Euroqol-5D questionnaire. A masked central committee adjudicated clinical outcomes. Patients and investigators were not masked to treatment allocation. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00491036. Between June 16, 2009, and March 3, 2012, 600 patients were assigned to IABP (n=301) or control (n=299). Of 595 patients completing 12 month follow-up, 155 (52%) of 299 patients in the IABP group and 152 (51%) of 296 patients in the control group had died (relative risk [RR] 1·01, 95% CI 0·86–1·18, p=0·91). There were no significant differences in reinfarction (RR 2·60, 95% CI 0·95–7·10, p=0·05), recurrent revascularisation (0·91, 0·58–1·41, p=0·77), or stroke (1·50, 0·25–8·84, p=1·00). For survivors, quality-of-life measures including mobility, self-care, usual activities, pain or discomfort, and anxiety or depression did not differ significantly between study groups. In patients undergoing early revascularisation for myocardial infarction complicated by cardiogenic shock, IABP did not reduce 12 month all-cause mortality. German Research Foundation; German Heart Research Foundation; German Cardiac Society; Arbeitsgemeinschaft Leitende Kardiologische Krankenhausärzte; University of Leipzig—Heart Centre; Maquet Cardiopulmonary; Teleflex Medical.

Quantum cascade lasers are compact, electrically pumped light sources in the technologically important mid-infrared and terahertz region of the electromagnetic spectrum 1 , 2 . Recently, the concept of topology 3 has been expanded from condensed matter physics into photonics 4 , giving rise to a new type of lasing 5 – 8 using topologically protected photonic modes that can efficiently bypass corners and defects 4 . Previous demonstrations of topological lasers have required an external laser source for optical pumping and have operated in the conventional optical frequency regime 5 – 8 . Here we demonstrate an electrically pumped terahertz quantum cascade laser based on topologically protected valley edge states 9 – 11 . Unlike topological lasers that rely on large-scale features to impart topological protection, our compact design makes use of the valley degree of freedom in photonic crystals 10 , 11 , analogous to two-dimensional gapped valleytronic materials 12 . Lasing with regularly spaced emission peaks occurs in a sharp-cornered triangular cavity, even if perturbations are introduced into the underlying structure, owing to the existence of topologically protected valley edge states that circulate around the cavity without experiencing localization. We probe the properties of the topological lasing modes by adding different outcouplers to the topological cavity. The laser based on valley edge states may open routes to the practical use of topological protection in electrically driven laser sources. A topological laser based on the valley degree of freedom in a compact photonic crystal can be pumped electrically, bringing topological physics concepts closer to real-life applications.

Three mechanisms for self-induced Ekman pumping in the interiors of mesoscale ocean eddies are investigated. The first arises from the surface stress that occurs because of differences between surface wind and ocean velocities, resulting in Ekman upwelling and downwelling in the cores of anticyclones and cyclones, respectively. The second mechanism arises from the interaction of the surface stress with the surface current vorticity gradient, resulting in dipoles of Ekman upwelling and downwelling. The third mechanism arises from eddy-induced spatial variability of sea surface temperature (SST), which generates a curl of the stress and therefore Ekman pumping in regions of crosswind SST gradients. The spatial structures and relative magnitudes of the three contributions to eddy-induced Ekman pumping are investigated by collocating satellite-based measurements of SST, geostrophic velocity, and surface winds to the interiors of eddies identified from their sea surface height signatures. On average, eddy-induced Ekman pumping velocities approach O (10) cm day −1 . SST-induced Ekman pumping is usually secondary to the two current-induced mechanisms for Ekman pumping. Notable exceptions are the midlatitude extensions of western boundary currents and the Antarctic Circumpolar Current, where SST gradients are strong and all three mechanisms for eddy-induced Ekman pumping are comparable in magnitude. Because the polarity of current-induced curl of the surface stress opposes that of the eddy, the associated Ekman pumping attenuates the eddies. The decay time scale of this attenuation is proportional to the vertical scale of the eddy and inversely proportional to the wind speed. For typical values of these parameters, the decay time scale is about 1.3 yr.

Despite major advances in the treatment of heart failure, cardiogenic shock (CGS) remains associated with substantial mortality. Recent data suggest that the TandemHeart percutaneous ventricular assist device (pVAD) may be useful in the management of CGS. The aim of this prospective randomized study was to test the hypothesis that the TandemHeart (pVAD) provides superior hemodynamic support compared with intraaortic balloon pumping (IABP). Forty-two patients from 12 centers presenting within 24 hours of developing CGS were included in the study and treated in an initial roll-in phase (n = 9) or randomized to treatment with IABP (n = 14) or TandemHeart pVAD (n = 19). Thirty patients (71%) had persistent CGS despite having an IABP in place at the time of study enrollment. Cardiogenic shock was due to myocardial infarction in 70% of the patients and decompensated heart failure in most of the remaining patients. The mean duration of support was 2.5 days. Compared with IABP, the TandemHeart pVAD achieved significantly greater increases in cardiac index and mean arterial blood pressure and significantly greater decreases in pulmonary capillary wedge pressure. Overall 30-day survival and severe adverse events were not significantly different between the 2 groups. In patients presenting within 24 hours of the development of CGS, TandemHeart significantly improves hemodynamic parameters, even in patients failing IABP. Larger-scale studies are required to assess the influence of improved hemodynamics on survival.