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Glacier- and snowpack-derived meltwaters are threatened by climate change. Features such as rock glaciers (RGs) are climatically more resilient than glaciers and potentially contain hydrologically valuable ice volumes. However, while the distribution and hydrological significance of glaciers is well studied, RGs have received comparatively little attention. Here, we present the first near-global RG database (RGDB) through an analysis of current inventories and this contains >51,000 RGs. Using the RGDB, we identify key data-deficient regions as research priorities (e.g., Central Asia). We provide the first approximation of near-global RG water volume equivalent and this is 62.02 ± 12.40 Gt. Excluding the Antarctic and Subantarctic, Greenland Periphery, and regions lacking data, we estimate a near-global RG to glacier water volume equivalent ratio of 1:618. Significant RG water stores occur in arid and semi-arid regions (e.g., South Asia East, 1:57). These results represent a first-order approximation. Uncertainty in the water storage estimates includes errors within the RGDB, inherent flaws in the meta-analysis methodology, and RG thickness estimation. Here, only errors associated with the assumption of RG ice content are quantified and overall uncertainty is likely larger than that quantified. We suggest that RG water stores will become increasingly important under future climate warming.

The deep sea is often viewed as a vast, dark, remote, and inhospitable environment, yet the deep ocean and seafloor are crucial to our lives through the services that they provide. Our understanding of how the deep sea functions remains limited, but when treated synoptically, a diversity of supporting, provisioning, regulating and cultural services becomes apparent. The biological pump transports carbon from the atmosphere into deep-ocean water masses that are separated over prolonged periods, reducing the impact of anthropogenic carbon release. Microbial oxidation of methane keeps another potent greenhouse gas out of the atmosphere while trapping carbon in authigenic carbonates. Nutrient regeneration by all faunal size classes provides the elements necessary for fueling surface productivity and fisheries, and microbial processes detoxify a diversity of compounds. Each of these processes occur on a very small scale, yet considering the vast area over which they occur they become important for the global functioning of the ocean. The deep sea also provides a wealth of resources, including fish stocks, enormous bioprospecting potential, and elements and energy reserves that are currently being extracted and will be increasingly important in the near future. Society benefits from the intrigue and mystery, the strange life forms, and the great unknown that has acted as a muse for inspiration and imagination since near the beginning of civilization. While many functions occur on the scale of microns to meters and timescales up to years, the derived services that result are only useful after centuries of integrated activity. This vast dark habitat, which covers the majority of the globe, harbors processes that directly impact humans in a variety of ways; however, the same traits that differentiate it from terrestrial or shallow marine systems also result in a greater need for integrated spatial and temporal understanding as it experiences increased use by society. In this manuscript we aim to provide a foundation for informed conservation and management of the deep sea by summarizing the important role of the deep sea in society.

Background The benefits of haptic feedback in laparoscopic surgery training simulators is a topic of debate in the literature. It is hypothesized that novice surgeons may not benefit from the haptic information, especially during the initial phase of learning a new task. Therefore, provision of haptic feedback to novice trainees in the early stage of training may be distracting and detrimental to learning. A controlled experiment was conducted to examine the effect of haptic feedback on the learning curve of a complex laparoscopic suturing and knot-tying task. Methods The ProMIS and the MIST-VR surgical simulators were used to represent conditions with and without haptic feedback, respectively. A total of 20 novice subjects (10 per simulator) were trained to perform suturing and knot-tying and practiced the tasks in 18 sessions of 1 h each. Results At the end of the 3-week training period, the subjects performed equally fast but more consistently with haptics (ProMIS) than without haptics (MIST-VR). The subjects showed a slightly higher learning rate and reached the first plateau of the learning curve earlier with haptic feedback. Conclusion In general, learning with haptic feedback was significantly better than learning without it for a laparoscopic suturing and knot-tying task, but only during the first 5 h of training. Haptic feedback may not be warranted in laparoscopic surgical trainers. The benefits of a shorter time to the first performance plateau and more consistent initial performance should be balanced with the cost of implementing haptic feedback in surgical simulators.

BackgroundDiversity, equity, and inclusion have been an intentional focus for SAGES well before the COVID-19 pandemic and the coincident societal recognition of social injustices and racism. Longstanding inequities within our society, healthcare, and the surgery profession have come to light in the aftermath of events that rose to attention around the time of Covid. In so doing, they have brought into focus disparities, injustices, and inequalities that have long been present in the field of surgery, selectively affecting the most vulnerable.MethodsThis White paper examines the current state of diversity within the field of surgery and SAGES (Society of American Gastrointestinal and Endoscopic Surgeons) approach and effort to pave the way forward to meaningful change. We delineate the imperative for diversity, equity, and inclusion for all. By all, we mean to be inclusive of the diversity of gender and sexual orientation, race, ethnicity, geography, sex, and disability in the field of surgery.ResultsSAGES is an organization that lives at the intersection of education and innovation. It has a vital role in assisting the surgical profession in addressing these issues and needs and being a force alongside others for sustained and necessary change. SAGES can only realize these goals through a commitment across all aspects of the organization to embed diversity, equity, and inclusion into our very fabric.ConclusionTrue diversity, equity, and inclusion within a surgical organization is vital for its longevity, growth, relevance, and impact. Unfortunately, the absence of DEI limits opportunity, robs the organization of collective intelligence in an environment in which its presence is critical, contributes to health inequities, and impoverishes all within the society and its value to all with whom it interfaces. SAGES is an organization that lives at the intersection of education and innovation. It has a vital role in assisting the surgical profession in addressing these issues and needs and being a force alongside others for sustained and necessary change. SAGES can only realize these goals through a commitment across all aspects of the organization to embed diversity, equity, and inclusion into our very fabric. Strategies like those highlighted in this White Paper, may be within our grasp and we can learn yet more if we remain in a place of humility and teachability in the future.

Chemical transport models (CTMs) driven with high-resolution meteorological fields can better resolve small-scale processes, such as frontal lifting or deep convection, and thus improve the simulation and emission estimates of tropospheric trace gases. In this work, we explore the use of the GEOS-Chem four-dimensional variational (4D-Var) data assimilation system with the nested high-resolution version of the model (0.5° × 0.67°) to quantify North American CO emissions during the period of June 2004–May 2005. With optimized lateral boundary conditions, regional inversion analyses can reduce the sensitivity of the CO source estimates to errors in long-range transport and in the distributions of the hydroxyl radical (OH), the main sink for CO. To further limit the potential impact of discrepancies in chemical aging of air in the free troposphere, associated with errors in OH, we use surface-level multispectral MOPITT (Measurement of Pollution in The Troposphere) CO retrievals, which have greater sensitivity to CO near the surface and reduced sensitivity in the free troposphere, compared to previous versions of the retrievals. We estimate that the annual total anthropogenic CO emission from the contiguous US 48 states was 97 Tg CO, a 14 % increase from the 85 Tg CO in the a priori. This increase is mainly due to enhanced emissions around the Great Lakes region and along the west coast, relative to the a priori. Sensitivity analyses using different OH fields and lateral boundary conditions suggest a possible error, associated with local North American OH distribution, in these emission estimates of 20 % during summer 2004, when the CO lifetime is short. This 20 % OH-related error is 50 % smaller than the OH-related error previously estimated for North American CO emissions using a global inversion analysis. We believe that reducing this OH-related error further will require integrating additional observations to provide a strong constraint on the CO distribution across the domain. Despite these limitations, our results show the potential advantages of combining high-resolution regional inversion analyses with global analyses to better quantify regional CO source estimates.

An experiment was conducted to determine the effect of the form of dietary fat (extracted or intact fat) and of dietary NDF on ileal and total tract endogenous losses of fat (ELF), on apparent ileal (AID) and apparent total tract digestibility (ATTD) of fat, and on true ileal (TID) and true total tract digestibility (TTTD) of fat in growing pigs. A cornstarch-based basal diet that contained 1.27% fat was prepared and 3 diets were formulated by adding 2.0, 4.0, or 6.0% extracted fat (corn oil) to the basal diet at the expense of cornstarch. Three additional diets were formulated by adding 3.1, 6.2, or 9.3% Solka-Floc (International Fiber Corp., North Tonawanda, NY) to the diet containing 4.0% corn oil at the expense of cornstarch. The remaining 4 diets were prepared by adding whole corn germ meal to the diet at the expense of defatted corn germ meal to contain 3.0, 6.0, or 9.0% intact fat. Solka-Floc was also included in this diet at the expense of cornstarch in an attempt to keep NDF constant. Eleven barrows (initial average BW of 38.1 ± 1.3 kg) were fitted with a T-cannula in the distal ileum, allotted to the 11 diets in an 11 x 11 Latin square design, and fed the diets at 3 times the energy requirement for maintenance. Increasing dietary extracted fat increased (linear and quadratic, P < 0.001) the AID and ATTD of fat. Increasing dietary intact fat also increased (linear and quadratic, P < 0.05) the AID and ATTD of fat. The average apparent digestibility of extracted fat (81.9%) was greater (P < 0.001) than that of intact fat (63.2%). Estimates of ELF were smaller (P < 0.05) for extracted fat than for intact fat at the end of the ileum and over the entire intestinal tract, but the TID (93.8%) and TTTD (94.2%) of extracted fat were greater (P < 0.05) than the TID (78.6%) and TTTD (84.1%) of intact fat. Increasing dietary extracted fat had no effects on the TID and TTTD of fat, but increasing dietary intact fat resulted in a quadratic reduction (P < 0.05) in the TTTD of fat. Increasing dietary NDF had a quadratic effect (P < 0.05) on the ATTD of fat but did not influence the AID, TID, and TTTD of fat. In conclusion, extracted fat induces a smaller amount of ELF and has a greater apparent and true digestibility than intact fat at the end of the ileum and over the entire intestinal tract. Purified NDF has little influence on apparent and true digestibility of fat.

We assess the impact of transport of pollution from midlatitudes on the abundance of ozone in the Arctic in summer 2006 using the GEOS‐Chem global chemical transport model and its adjoint. We find that although the impact of midlatitude emissions on ozone abundances in the Arctic is at a maximum in fall and winter, in July transport from North America, Asia, and Europe together contributed about 25% of surface ozone abundances in the Arctic. Throughout the summer, the dominant source of ozone in the Arctic troposphere was photochemical production within the Arctic, which accounted for more than 50% of the ozone in the Arctic boundary layer and as much as 30%–40% of the ozone in the middle troposphere. An adjoint sensitivity analysis of the impact of NOx emissions on ozone at Alert shows that on synoptic time scales in both the lower and middle troposphere, ozone abundances are more sensitive to emissions between 50°N and 70°N, with important influences from anthropogenic, biomass burning, soil, and lightning sources. Although local surface NOx emissions contribute to ozone formation, transport of NOx in the form of peroxyacetyl nitrate (PAN) from outside the Arctic and from the upper troposphere also contributed to ozone production in the lower troposphere. We find that in late May and June the release of NOx from PAN decomposition accounted for 93% and 55% of ozone production at the Arctic surface, respectively. Key Points Midlatitude source regions contribute 10‐25% of Arctic ozone in summer On short time scales, Arctic O3 is most sensitive to NOx emissions at 50‐70N NOx transported as PAN constitutes most of O3 produced in the Arctic spring

Rapid industrialization in Asia in the last two decades has resulted in a significant increase in Asian ozone (O3) precursor emissions with likely a corresponding increase in the export of O3 and its precursors. However, the relationship between this increasing O3, the chemical environment, O3 production efficiency, and the partitioning between anthropogenic and natural precursors is unclear. In this work, we use satellite measurements of O3, CO and NO2 from TES (Tropospheric Emission Spectrometer), MOPITT (Measurement of Pollution In The Troposphere) and OMI (Ozone Monitoring Instrument) to quantify O3 precursor emissions for 2006 and their impact on free tropospheric O3 over northeastern Asia, where pollution is typically exported globally due to strong westerlies. Using the GEOS-Chem (Goddard Earth Observing System Chemistry) global chemical transport model, we test the modeled seasonal and interannual variation of O3 based on prior and updated O3 precursor emissions where the updated emissions of CO and NOx are based on satellite measurements of CO and NO2. We show that the observed TES O3 variability and amount are consistent with the model for these updated emissions. However, there is little difference in the modeled ozone between the updated and prior emissions. For example, for the 2006 June time period, the prior and posterior NOx emissions were 14% different over China but the modeled ozone in the free troposphere was only 2.5% different. Using the adjoint of GEOS-Chem we partition the relative contributions of natural and anthropogenic sources to free troposphere O3 in this region. We find that the influence of lightning NOx in the summer is comparable to the contribution from surface emissions but smaller for other seasons. China is the primary contributor of anthropogenic CO, emissions and their export during the summer. While the posterior CO emissions improved the comparison between model and TES by 32%, on average, this change also had only a small effect on the free tropospheric ozone. Our results show that the influence of India and southeastern Asia emissions on O3 pollution export to the northwestern Pacific is sizeable, comparable with Chinese emissions in winter, about 50% of Chinese emissions in spring and fall, and approximately 20% of the emissions in the summer.