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This corrects the article DOI: 10.1038/srep42429.

Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore's law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + "Molecular") architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

The scale of the decarbonisation challenge to meet the Paris Agreement is underplayed in the public arena. It will require precipitous emissions reductions within 40 years and a new carbon sink on the scale of the ocean sink. Even then, the world is extremely likely to overshoot. A catastrophic failure of policy, for example, waiting another decade for transformative policy and full commitments to fossil-free economies, will have irreversible and deleterious repercussions for humanity’s remaining time on Earth. Only a global zero carbon roadmap will put the world on a course to phase-out greenhouse gas emissions and create the essential carbon sinks for Earth-system stability, without which, world prosperity is not possible.

The global perspective presented here is built on earlier papers discussing the dynamics of the upper branch of the Hadley cell in the two solsticial seasons. The role of the tropics is made explicit in a conceptual model that is presented and evaluated. The fluctuation of deep tropical convection in longitude and time is seen as crucial. The filamentary outflows from such convective events move westward and across the equator deep into the winter hemisphere. The horizontal tilt of the cross-equatorial flow implies a significant upper-tropospheric flux of westerly momentum from the winter tropics to the summer hemisphere. These properties are related to the cross-equatorial propagation of wave activity triggered by deep tropical convection in the summer hemisphere. The filaments carry with them near-equatorial values of absolute vorticity and potential vorticity. After turning anticyclonically, some filaments move eastward and poleward to the equatorial edge of the winter subtropical jet. There is strong evidence they can interact with the eddies on this jet and enhance their poleward westerly momentum flux. In the global perspective, tropical and extratropical systems and the interaction between them are all important for the dynamics of the upper branch of the Hadley cell. significance statement: The Hadley cell is the large-scale overturning in the atmosphere with air in the upper troposphere moving from the equatorial region to near 30° in the winter hemisphere. In the standard view it is midlatitude weather systems that are responsible for removing angular momentum from this upper branch of the Hadley cell. Here it is proposed that tropical systems and their interaction with the midlatitude systems are also important. Insight into the role of the tropics in the dynamics of the Hadley cell can be obtained by considering it as the sum of many events of active deep convection occurring in different longitudes and at different times. [ABSTRACT FROM AUTHOR]

Cryogenic operation of complementary metal oxide semiconductor (CMOS) silicon transistors is crucial for quantum information science, but it brings deviations from standard transistor operation. Here, we report on sharp current jumps and stable hysteretic loops in the drain current as a function of gate voltage VG for both n- and p-type commercial-foundry 180-nm-process CMOS transistors when operated at voltages exceeding 1.3 V at cryogenic temperatures. The physical mechanism responsible for the device bistability is impact ionization charging of the transistor body, which leads to effective back-gating of the inversion channel. This mechanism is verified by independent measurements of the body potential. The hysteretic loops, which have a >107 ratio of high to low drain current states at the same VG, can be used for a compact capacitorless single-transistor memory at cryogenic temperatures with long retention times. [ABSTRACT FROM AUTHOR]

The seminal theory for the Hadley Cells has demonstrated that their existence is necessary for the reduction of tropical temperature gradients to a value such that the implied zonal winds are realisable. At the heart of the theory is the notion of angular momentum conservation in the upper branch of the Hadley Cells. Eddy mixing associated with extratropical systems is invoked to give continuity at the edge of the Hadley Cell and to reduce the subtropical jet by a factor of three or more to those observed. In this article a detailed view is presented of the dynamics of the June–August Hadley Cell, as given by ERA data for the period 1981–2010, with an emphasis on the dynamics of the upper branch. The steady and transient northward fluxes of angular momentum have a very similar structure, both having a maximum on the Equator and a reversal in sign near 12°S, with the transient flux merging into that associated with eddies on the winter subtropical jet. In the northward absolute vorticity flux, the Coriolis torque is balanced by both the steady and transient fluxes. The overturning circulations that average to give the Hadley Cell are confined to specific longitudinal regions, as are the steady and transient momentum fluxes. In these regions, both intraseasonal and synoptic variations are important. The dominant contributor to the Hadley Cell is from the Indian Ocean and west Pacific regions, and the maxima in OLR variability and meridional wind in these regions have a characteristic structure associated with the Westward‐moving Mixed Rossby–Gravity wave. Much of the upper tropospheric motion into the winter hemisphere occurs in filaments of air from the summer equatorial region. These filaments can reach the winter subtropical jet, leading to the strengthening of it and of the eddies on it, implying strong tropical–extratropical interaction. [ABSTRACT FROM AUTHOR]

In this paper a simple 2D linear quasigeostrophic model is used to investigate how the development of local confined cyclonic perturbations is dependent on the perturbation scale, location, and tilt in Eady-type basic states. It is found that the initial growth of the perturbation can be maximized by reducing both the vertical and horizontal scale and using a 'midtropospheric' vertical location. 'Potential vorticity (PV) thinking' suggests the concept of 'PV unshielding' to explain this result. Adding a meridional gradient of basic-state PV lowers the vertical location of perturbations that optimally excite sustained growth. This can be understood by considering the behavior of the upward and downward propagating parts of the initial perturbation. It is found that the importance of the initial perturbation tilt is diminished for confined perturbations. It is shown that diabatic heating in a vertically confined region can lead to a perturbation that exhibits rapid growth. The findings in this paper lay some foundations for understanding calculated optimal growth structures, such as the singular vectors produced routinely by the European Centre for Medium-Range Weather Forecasts.

The magnitudes of the challenges facing electron-based metrology for post-CMOS technology are reviewed. Directed self-assembly, nanophotonics/plasmonics, and resistive switches and selectors are examined as exemplars of important post-CMOS technologies. Materials, devices, and architectures emerging from these technologies pose new metrology requirements: defect detection, possibly subsurface, in soft materials, accurate measurement of size, shape, and roughness of structures for nanophotonic devices, contamination-free measurement of surface-sensitive structures, and identification of subtle structural, chemical, or electronic changes of state associated with switching in non-volatile memory elements. Electron-beam techniques are examined in the light of these emerging requirements. The strong electron-matter interaction provides measurable signals from small sample features, rendering electron-beam methods more suitable than most for nanometer-scale metrology, but as is to be expected, solutions to many of the measurement challenges are yet to be demonstrated. The seeds of possible solutions are identified when they are available. [ABSTRACT FROM AUTHOR]

The behaviour of the eddy-driven jet over the Atlantic sector during the winter season is analyzed for the ERA-Interim reanalysis and the coupled and atmosphere-only configuration of HadGEM3-GC2-the climate model in use at the Met Office. The trimodal distribution that characterizes the jet-stream structure in terms of its preferred locations is reproduced with good accuracy by the model, although a distinct bias towards the high-latitude position is observed. Two different scenarios are found to contribute to this bias. One occurs when the jet shifts from its southern regime, whereby it settles too far north and for too long compared with the reanalysis. The other is associated with the exit from the central latitude regime, with too many events shifting poleward rather than equatorward. Excessively large lower tropospheric eddy heat fluxes during these transitions may account for the jet errors, even though the heat fluxes do not exhibit a climatological bias. Interestingly, these biases are weaker when the atmosphere model is forced with observed sea-surface temperatures (SSTs), suggesting that either it is vital to have the correct SST distribution or ocean-atmosphere coupling plays a key role in the biases. Additional analysis revealed that the Pacific jet exit is biased south in the coupled model and that this contributes to the Atlantic bias. Anomalously warm SSTs in the Gulf Stream region may be acting together with the Pacific bias in fostering anomalous activity in low-level eddy heat fluxes. [ABSTRACT FROM AUTHOR]

Context: Consumer reports in health care are a relatively recent phenomenon. Primarily designed to assist consumers in making more informed decisions about their personal health care, they appear to have an important by-product-they led to positive changes in the behavior of clinicians and health care delivery organizations. While there has been much speculation on their impact on health care consumer behavior, consumer reports offer an effective strategy in improving the quality of patient care.Objective: To examine the impact of an obstetrics consumer report developed and issued by the Missouri Department of Health on hospital behavior.Design and Setting: A retrospective study of hospital behavior using both primary survey and secondary clinical data.Participants: Consumer reports were issued in 1993 to all Missouri hospitals providing obstetrical services (n=90). A survey was conducted a year later, and the results were analyzed with other available data to determine the effect of the report. Two hospitals discontinued obstetrical services by the time of the survey; of the remaining 88 hospitals, 82 (93%) responded to the survey.Main Outcome Measures: The following outcomes were examined: (1) number and percentage of hospitals that previously did not have services at the time report was issued, but had, or planned to have, services after a guide was published; (2) the percentage of obstetrical policies that were changed, planned to change, or are under discussion for change (car seat program, obstetrical follow-up services, formal transfer agreement, nurse educator for breast-feeding, and availability of tubal ligations); and (3) clinical outcomes, including satisfaction, appropriateness of charges, and the rates of cesarean delivery, high-risk infant transfer, ultrasound, vaginal birth after cesarean, very low birth weight, and newborn death.Results: Within 1 year of the report, approximately 50% of hospitals that did not have car seat programs, formal transfer agreements, or nurse educators for breast-feeding prior to the report either instituted or planned to institute these services. Hospitals in competitive markets that did not offer one of these services at the time of the report were more likely to institute a service and/or were about twice as likely to consider improving several indicators. Clinical outcome indicators all improved in the expected direction.Conclusion: Public release of consumer reports may be useful not only in assisting consumers to make informed health care choices, but also in facilitating improvement in the quality of hospital services offered and care provided. Changes occur especially in competitive markets. [ABSTRACT FROM AUTHOR]

In this article, Northern Hemisphere winter midlatitude blocking is analysed through its wave-breaking characteristics. Rossby wave breaking is identified as a key process in blocking occurrence, as it provides the mechanism for the meridional reversal pattern typical of blocking. Two indices are designed to detect the major properties of wave breaking, i.e. the orientation (cyclonic/anticyclonic-direction of breaking or DB index) and the relative contribution of air masses (warm/cold-relative intensity or RI index). The use of the DB index differentiates between the anticyclonic cases over Europe and Asia and the cyclonic events over the oceanic basins. One of the three regions displaying cyclonic type was found over the Atlantic Ocean, the other two being over the Pacific Ocean. The first of these is located over the western side of the Pacific and is dominated by warm air extrusions, whereas the second is placed northward of the exit region of the jet stream, where the meridional θ gradient is much weaker. Two European blocking types have been detected using the RI index, which separates out the cases dominated by warm and cold air masses. The latter cases in particular exhibited a well-structured dipole, with associated strong anomalies in both temperature and precipitation. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Routine use of the Shoemaker, McLean, and Pratt (SMP) lime buffer method resulted in chronic problems with electrode reference junction degradation, stability of readings relative to contact time, and generation of hazardous waste. During method recalibration, the Mehlich buffer was chosen for parallel evaluation with SMP, with the goal of improving method performance and eliminating of hazardous waste. The Mehlich buffer was modified by substituting calcium (Ca) for barium (Ba). The modified Mehlich (MM) buffer was found to be identical to the original with respect to buffering power and linearity over an extended pH range of 3.0-6.6. Seven agronomic soils were incubated with eight rates of calcium carbonate for 90 days. Regression analysis was performed to predict lime requirement (LR) to several target pH levels, based on pH measured in each buffer alone or in both water and buffer. Slightly better predictability was obtained using multiple regressions, with R2>0.95 in all cases. Significant but minor differences occurred between the newly calibrated buffers in extended comparisons. The MM buffer was superior to the SMP during routine usage, with fewer adverse effects on electrodes and the elimination of hazardous waste. [ABSTRACT FROM AUTHOR]

A comprehensive climatology of Northern Hemisphere blocking is described based on a PV–θ wave-breaking index at the latitude of the climatological storm track and using the 40-yr ECMWF Re-Analysis (ERA-40) dataset. The general characterization of blocking regions is in agreement with most other studies, though more detail is provided here. In the annual average, blocking is most prevalent in the large region from the eastern Atlantic Ocean through Europe to central Asia with a secondary region in the central and eastern Pacific Ocean. Using a blocking criterion with the requirement for both longitudinal extent and temporal persistence, the peak in the frequency is in the Scandinavian region, where 24% of the days are characterized by blocking. In the east Pacific maximum, the corresponding number is 7%. However, there is considerable and very important interannual variability. The decay rate in the number of blocking events lasting at least a specified number of days is significantly less over Europe than elsewhere. However, the average intensity of blocking episodes is slightly higher in the east Pacific. The mean annual cycle of blocking is quite complex. Over most of Europe it continues through the year, with maximum intensities in the autumn and winter. To both the east and west, over the western Atlantic and Asia, there are two periods in the year of highest blocking frequency. Similar two-cycle behavior is found in the eastern Pacific region. The relationship of blocking with the storm track and the mean planetary-scale geopotential ridges is considered, and the evidence that blocking is a particular phenomenon with its own nonlinear dynamics is discussed. [ABSTRACT FROM AUTHOR]

The morphology of regional blocking in the Northern Hemisphere is discussed using the 40-yr ECMWF Re-Analysis (ERA-40) dataset and a measure of blocking based on the reversal at storm-track latitudes of meridional θ contrasts on a potential vorticity (PV) surface representative of the tropopause. The focus is on cyclonic and anticyclonic Rossby wave breaking that is inherent to the blocking development, and the extent to which this is determined by the climatological jet position and the ambient shears. More generally, the importance of the climatological planetary scale is discussed. The approach is mainly through composite behavior, but informed by consideration of many individual events. A diversity of behavior is found with longitude in both winter and summer, and there is a striking reversal of the sense of the wave breaking between the two seasons that is generally consistent with the difference in the jet locations. Preferred behaviors are found in various regions and seasons, and retrogression of blocking is discussed. [ABSTRACT FROM AUTHOR]

Rossby wave breaking on the dynamical tropopause in the Southern Hemisphere (the -2-PVU surface) is investigated using the ERA-40 dataset. The indication of wave breaking is based on reversal in the meridional gradient of potential temperature, and persistent large-scale wave breaking is taken as a strong indication that blocking may be present. Blocking in the midlatitudes is found to occur predominantly during wintertime in the Pacific and is most vigorous in the east Pacific, while during summertime, the frequency of blocking weakens and its extent becomes confined to the west Pacific. The interannual variability of blocking is found to be high. Wave breaking occurs most frequently on the poleward side of the polar jet and has some, but not all, of the signatures of blocking, so it is referred to as high-latitude blocking. In general, cyclonic wave breaking occurs on the poleward side of the polar jet, otherwise anticyclonic breaking occurs. However, at least in wintertime, wave breaking in the New Zealand/west to mid-Pacific sector between the polar and subtropical jets is a mixture between cyclonic and anticyclonic types. Together, episodes of wave breaking and enhanced westerly flow describe much of the variability in the seasonal Antarctic Oscillation (AnO) index and give a synoptic manifestation of it with a focus on the date line and Indian Ocean that is in agreement with the centers of action for the AnO. During summertime, anticyclonic wave breaking in the upper troposphere is also to be found near 30°S in both the Pacific and Atlantic, and appears to be associated with Rossby waves propagating into the subtropics from the New Zealand region. [ABSTRACT FROM AUTHOR]