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As ice sheets load Earth's surface, they produce ice‐marginal depressions which, when filled with meltwater, become proglacial lakes. We include self‐consistently evolving proglacial lakes in a glacial isostatic adjustment (GIA) model and apply it to the Laurentide ice sheet over the last glacial cycle. We find that the locations of modeled lakes and the timing of their disappearance is consistent with the geological record. Lake loads can deflect topography by >10 m, and volumes collectively approach 30–45 cm global mean sea‐level equivalent. GIA increases deglaciation‐phase lake volume up to five‐fold and average along‐ice‐margin depth ≤90 m compared to glaciation‐phase ice volume analogs—differences driven by changes in the position and size of the peripheral bulge. Since ice‐marginal lake depth affects grounding‐line outflow, GIA‐modulated proglacial lake depths could affect ice‐sheet mass loss. Indeed, we find that Laurentide ice‐margin retreat rate sometimes correlates with proglacial lake presence, indicating that proglacial lakes aid glacial collapse. Plain Language Summary: The Laurentide ice sheet grew to its greatest extent during the last glacial maximum, covering most of Canada and the northern part of the US. During its existence, lakes formed adjacent to the ice sheet as seasonal melt water filled the topography around its edge. As the ice sheet grew and melted it changed the topography of Earth's surface by warping the ground beneath the ice sheet and around its edges. In this paper we investigate how this topographic change affected lakes around the ice sheet. We find that it caused lakes to be much bigger during the deglaciation, when the ice sheet retreated and left lows in the topography that took thousands of years after the retreat to fully rebound. We also find that these lakes were deeper at the edge of the ice sheet as the ice sheet collapsed than as it grew, which might have caused faster ice sheet collapse since ice sheets lose mass faster if they end in a lake rather than if they end on land. Our finding shows that lakes might play an important role in how fast past ice sheets grew and collapsed. Key Points: We self‐consistently model proglacial lakes that form around the Laurentide ice sheet over the last glacial cycleGlacial isostatic adjustment increases the volume and lake depth of proglacial lakes during the deglaciation compared to the glaciationWhen the ice margin retreated over areas of low‐lying topography, ice retreat was faster in areas that bordered proglacial lakes [ABSTRACT FROM AUTHOR]

In recent years, NASA has shown a renewed interest in Lunar exploration. This renewed interest is expected to spawn a new era of exploration into the solar system, as well as generate new residual technologies for earth application. A review of experiences on the prior Apollo missions shows that there are significant challenges associated with returning to and establishing a base for humans in the harsh Lunar environment. The present article is a high level overview of the effort to return to the Moon, in the context of a larger effort towards human expansion farther into the solar system. Also included is a review of technical challenges associated with returning to the Moon. [ABSTRACT FROM AUTHOR]

Lower oesophageal sphincter pressures in healthy volunteers were measured by a rapid pull-through technique during intravenous infusion of the histamine H2-receptor antagonist, cimetidine. No consistent effects on sphincter pressure were observed which are liable to be of clinical importance. Serum gastrin concentrations during cimetidine infusion were measured by radioimmunoassay and showed no significant variation. In a further series of experiments, the response of the lower oesophageal sphincter to intravenous bolus injection of pentagastrin was measured before and during cimetidine infusion. Cimetidine infusion had no significant effect on the sphincter response to pentagastrin. [ABSTRACT FROM PUBLISHER]

Arctic shorelines are vulnerable to climate change impacts as sea level rises, permafrost thaws, storms intensify, and sea ice thins. Seventy-five years of aerial and satellite observations have established coastal erosion as an increasing Arctic hazard. However, other hazards at play-for instance, the cumulative impact that sea-level rise and permafrost thaw subsidence will have on permafrost shorelines-have received less attention, preventing assessments of these processes' impacts compared to and combined with coastal erosion. Alaska's Arctic Coastal Plain (ACP) is ideal for such assessments because of the high-density observations of topography, coastal retreat rates, and permafrost characteristics, and importance to Indigenous communities and oilfield infrastructure. Here, we produce 21st-century projections of Arctic shoreline position that include erosion, permafrost subsidence, and sea-level rise. Focusing on the ACP, we merge 5 m topography, satellite-derived coastal lake depth estimates, and empirical assessments of land subsidence due to permafrost thaw with projections of coastal erosion and sea-level rise for medium and high emissions scenarios from the Intergovernmental Panel on Climate Change's AR6 Report. We find that by 2100, erosion and inundation will together transform the ACP, leading to 6-8x more land loss than coastal erosion alone and disturbing 8-11x more organic carbon. Without mitigating measures, by 2100, coastal change could damage 40 to 65% of infrastructure in present-day ACP coastal villages and 10 to 20% of oilfield infrastructure. Our findings highlight the risks that compounding climate hazards pose to coastal communities and underscore the need for adaptive planning for Arctic coastlines in the 21st century., Competing Interests: Competing interests statement:The authors declare no competing interest.

Objective: To describe a case of papillary carcinoma of the thyroid with fibromatosislike stroma, emphasize the need for a diligent search for papillary thyroid cancer in the presence of a fibroproliferative lesion, highlight the peculiar hormonal response of the stromal component, and review the pertinent literature., Methods: We present the clinical, laboratory, radiologic, and pathologic findings in a patient with papillary carcinoma of the thyroid with fibromatosislike stroma and review the related published material., Results: A 29-year-old woman presented to our surgical department because of a large mediastinal mass. She underwent surgical removal of the mass by means of a median sternotomy and neck extension. Pathology examination revealed macroscopically tan scarlike tissue, which by histologic study consisted of a dominant fibroproliferative lesion overshadowing a minor component of papillary carcinoma of the thyroid. Further neck exploration with total thyroidectomy revealed multifocal papillary carcinoma of the thyroid. Postoperatively, the patient received radioiodine treatment. A local and aggressive recurrent tumor was observed during a subsequent pregnancy; the lesion was not amenable to complete resection but fascinatingly responded to antiestrogen therapy (orally administered tamoxifen)., Conclusion: The presence of a fibroproliferative lesion could be misleading. A diligent search should be made for a papillary thyroid carcinoma component within fibromatosislike stroma. The mode of manifestation of the tumor and its response to hormonal manipulation are distinctive features of this case.

Dehydroepiandrosterone sulfate (DHAS) has been measured by radioimmunoassay in 100 breast cyst fluids obtained from 82 women. Values ranged from 1.5 to 1,155 microM with a median of 140 microM. These concentrations are in excess of those for plasma but are comparable or less than values for breast secretions obtained by nipple aspiration. Levels of DHAS in cyst fluid were not significantly affected by age, menopausal status, or parity of the subject or by the volume of cyst fluid obtained. In patients with multiple cysts, DHAS values from cysts aspirated from the same breast on the same data were relatively comparable, but wide variations were frequently observed between cysts aspirated on different occasions from the same breast and between cysts from different breasts of the same patient, whether sampled simultaneously or sequentially. Such variability must complicate comparative studies among women.

Wide variations in the concentrations of IgA, IgG, lactoferrin, lysozyme and albumin were found in 96 cyst fluids obtained from 75 patients with gross cystic disease of the breast. Sedimentation coefficient determination were performed on 19 of the cyst fluids with the highest IgA concentrations in an attempt to discover the basis for the wide variation and two types of cyst fluids were found: cyst fluids that resembled external secretions such as colostrum of milk with the IgA wholly or predominantly in the 11S (secretory) form, and low concentrations of IgG and albumin, and cyst fluids that resembled serum with the IgA wholly or predominantly in the 7S (serum) form, and high concentrations of IgG and albumin. Some cyst fluids contained low concentrations of all proteins measured, and no relationship was observed between the concentrations of the proteins studied, and age, parity or menstrual status.

Twenty-two instances of diaphragmatic rupture secondary to blunt thoracoabdominal trauma were seen at the Trauma Unit of the Health Sciences Centre, Winnipeg, Manitoba, Canada during a 30 year period. Diaphragmatic laceration occurred in the right leaf in 11, in the left in ten, and in both sides in one instance. In 14, the diagnosis was made and repair effected within 24 hours of presentation. Seven were diagnosed and treated from three days to several years after the injury. Two patients died soon after admission. They were victims of multiple intra-abdominal as well as intrathoracic injuries. Repair was generally effected through a laparotomy during the immediate post-traumatic period. Thoracotomy was used in those diagnosed after the latent interval. The diagnosis of diaphragmatic disruption should be considered in any patient suffering from blunt thoracoabdominal trauma. Usually a roentgenogram of the chest will confirm the suspected injury. In contradistinction to most of the reported series, our experience indicates that right diaphragmatic injuries are more common than what is usually thought.