Are we saving water? Simple methods for assessing the effectiveness of groundwater conservation measures

Substantial storage reductions by irrigation pumping in many of the world’s major aquifers jeopardize future food production. As a result, new conservation measures are being utilized to reduce pumping and extend aquifer lifespans. The key question is how effective are these practices in attaining true water conservation (i.e., water use reduction) for a given area? Relationships between pumping and precipitation help provide an answer, as precipitation explains most of the variation in annual irrigation water use for aquifers in semi-arid to sub-humid climates when surface water supplies are limited. Our objective is to utilize correlations between radar precipitation and irrigation groundwater use at a range of spatial scales to assess the effectiveness of conservation approaches in the High Plains aquifer in the central USA. Linear regressions between pumping and precipitation for a conservation area established in 2013 in northwest Kansas indicate that water use and water use per irrigated area were over 27 % less and 25 % less, respectively, during 2013–2021 compared to the same climatic conditions during 2005–2012. Similar regressions found over a 38 % reduction and 23 % reduction in irrigation water use and use per irrigated area, respectively, during 2018–2021 compared to the same conditions during 2005–2017 in a west-central Kansas county with conservation areas. A decrease in irrigated area accounted for most of the difference between these reductions. Higher R2 values after conservation area establishment imply that irrigation tracks precipitation better due to use of soil moisture sensors and other measures as part of increased irrigation efficiency and enhanced water management. The precipitation and water use relationships, which are statistically significant for a wide range of spatial scales, have great potential for assessing the effectiveness of conservation practices in areas with high-quality water use and precipitation data

Intrahistiocytic Storage of Clofazimine Crystals in a Cat

A 13-year-old castrated male Maine coon cat with a 5-year history of atypical mycobacteriosis was euthanized and submitted for necropsy. The cat had been kept in clinical remission since diagnosis using a combination of the antimycobacterial drug clofazimine and additional multimodal antimicrobial therapy. Grossly, tissues were diffusely discolored red-brown to yellow. Histologically, the myocardial interstitum was expanded by numerous, often multinucleated cells, which were distended by uniformly shaped acicular cytoplasmic spaces. These cells were immunopositive for CD18 and immunonegative for desmin, suggesting a histiocytic rather than muscular origin. Macrophages in other tissues contained similar acicular spaces. Ultrastructurally, the spaces were surrounded by 2 lipid membranes, resembling an autophagosome. Based on the clinical history and histologic, immunohistochemical, and ultrastructural data, we diagnosed clofazimine crystal storage. To our knowledge, this is the first report of clofazimine storage in a cat or within myocardial interstitial macrophages

Preferred strategies for secondary infrainguinal bypass: Lessons learned from 300 consecutive reoperations

AbstractPurpose: To determine the optimal surgical strategies in reoperative infrainguinal bypass, we reviewed our results in 300 consecutive secondary bypasses in 251 patients operated on between Jan. 1, 1975, and Nov. 1, 1993.Methods: There were 168 men (67%) and 83 women (33%), with a mean age of 64.8 years and a typical distribution of risk factors including smoking (76.4%), diabetes (33.7%), and coronary artery disease (47.1%). The indications for surgery were limb-threatening ischemia in 83.5% and severe claudication in 16.5% of patients. The majority of conduits (n = 213) were autogenous vein and were composed of a single segment of greater saphenous vein in 121 bypasses (57%) and various alternative veins including composite, arm, and lesser saphenous vein in 92 bypasses (43%). Prosthetic conduits included 69 polytetrafluoroethylene, 16 umbilical vein, and two Dacron grafts.Results: There was one perioperative death (0.3%) and a 25% total morbidity rate including a 1.7% myocardial infarction rate. There was a 28.6% early (<30 days) graft failure and 10.7% early amputation rate for prosthetic bypass grafts compared with 13.6% early graft failure and 5.6% early amputation rates for vein grafts. Autogenous vein bypasses had higher 5-year secondary patency rates than had prosthetic grafts (51.5% ± 4.6% vs 27.4% ± 6.1%, p < 0.001). Results with autogenous vein bypass improved significantly from the 1975 to 1984 to the 1985 to 1993 interval with 5-year secondary patency rates increasing from 38.3% ± 6.9% to 59.1% ± 5.8% (p = 0.017) and 5-year limb-salvage rates increasing from 40.4% ± 7.6% to 72.4% ± 6.6% (p < 0.001). Vein grafts to the popliteal and tibial outflow levels had equivalent long-term results. Vein grafts completed for claudication demonstrated results superior to those for limb salvage, with a 5-year secondary patency rate of 75.8% ± 8.1% versus 52.3% ± 7.9% (p = 0.048). Secondary autogenous vein bypass grafting performed after early primary graft failure (< 3 months) did particularly poorly, with only a 27.2% ± 7.7% 4-year secondary patency rate. Greater saphenous veins tended to perform better than alternative vein bypasses, with a 5-year secondary patency rate of 68.5% ± 6.0% compared with 48.3% ± 10.5% (p = 0.09) and a 5-year limb-salvage rate of 77.8% ± 7.4% versus 54.2% ± 11.8% (p = 0.046).Conclusions: When patients suffer a recurrence of limb-threatening ischemia at the time of infrainguinal graft failure, aggressive attempts at secondary revascularization with autogenous vein are warranted based on the low surgical morbidity and mortality rates and the improved patency and limb salvage rates that are currently attainable. (J VASC SURG 1995;21:282-95.

The impact of patient age and aortic size on the results of aortobifemoral bypass grafting1 1Competition of interest: none.Published online Mar 6, 2003

AbstractObjectives: On the basis of the widespread belief that aortobifemoral bypass (ABF) represents the optimal mode of revascularization for patients with diffuse aortoiliac disease, vascular surgeons are often aggressive about its application in young adults. We undertook this retrospective evaluation of ABFs performed from 1980 to 1999 to determine whether the results justify this approach. Patients of less than 50 years of age (n = 45) were compared with those aged 50 to 59 years (n = 93) and those aged more than 60 years (n = 146).Results: Younger patients were more likely to undergo operation for claudication than were older patients (72% versus 59% and 55%; P < .04). Younger patients were significantly more likely to be smokers (87%) but less likely to have diabetes, hypertension, or cerebrovascular disease. Bypasses were constructed in an end-to-end fashion in 71.1% of patients of less than 50 years versus 68.8% and 71.2% of older patients (P = not significant). The mean diameter of aortic grafts was significantly smaller in younger patients (14.6 mm) than in older patients (15.6 mm and 15.5 mm; P < .01). The need for a subsequent infrainguinal reconstruction was highest in the youngest patients (24% versus 17% and 7%; P < .01). Surgical mortality rates were low in all groups (0%, 1%, and 2.0% for increasing age groups; P = not significant). Five-year primary and secondary patency rates increased significantly with each increase in age interval: 5-year primary patency rate: less than 50 years, 66% ± 8%; 50 to 59 years, 87% ± 5%; more than 60 years, 96% ±2% (P < .05 for all comparisons). Five-year secondary patency rates were: less than 50 years, 79% ± 7%; 50 to 59 years, 91% ± 4%; more than 60 years, 98% ± 2% (P < .05 for all comparisons). Five-year survival rate was comparable in all three groups: less than 50 years, 93% ± 5%; 50 to 59 years, 92% ± 4%; more than 60 years, 87% ± 4% (P = not significant).Conclusion: Increased virulence of aortic disease, smaller aortic size, and more progressive infrainguinal disease may all negatively impact the results of ABF in younger patients. Although 5-year results are acceptable, increased caution is warranted in the routine application of ABF in young patients without limb-threatening ischemia

Importance of a sound hydrologic foundation for assessing the future of the High Plains Aquifer in Kansas

This is the published version. Copyright National Academy of SciencesSteward et al. (1) assess the hydrologic and agricultural future of the High Plains Aquifer. We have many concerns about hydrologic aspects of their study and describe the most significant here. The authors state “…the lines of recharge plus storage in Fig. 1C very closely approximate the recent data points of metered groundwater pumping….” That is not correct, as is clear from a comparison of reported pumping data (diamonds) and the authors’ calculated groundwater use (solid line) for the SW region. There is a systematic deviation (authors’ calculated use is increasing, whereas reported metered pumping data are decreasing), which persists even when uncertain pre-1990 pumping data are neglected. The authors’ groundwater use is also markedly inconsistent with common experiences in western Kansas (2). The 2020–2025 (SW) and 2025–2030 (NW) peaks in the authors’ groundwater use are simply a product of their logistic function representation (maximum use at normalized thickness of 0.5) and are in dramatic contrast to recorded pumping trends. Given that calculated groundwater use is input into the agricultural models, we question all of the agricultural projections. The authors provide no objective basis for accepting the logistic function as an accurate tool for projecting water level declines. The comparisons in their table S1 do little to substantiate the use of the function given that the authors (i) adjust two parameters per well; (ii) adjust parameters at each well independently of the other 1,600 wells; and (iii) in aggregate, only assess the first 30% of depletion. A number of alternative functions could be found that would produce similar agreement with existing data but markedly different future projections. We note the circularity of including extrapolated 2060 values in the dataset used to develop logistic curves that are then used to make future projections. The authors state “…and measurement points were added at 1930 and 2060 from a linear extrapolation of observations while keeping these points within the saturated aquifer.” We are concerned about the sensitivity of future projections to inclusion of 1930 and 2060 “measurements” and to the process (unexplained) for “keeping these points within the saturated aquifer.” The authors state that “We computed recent recharge rates to preserve conservation of mass….” That cannot be correct, as is clear from a comparison of reported pumping data (diamonds) and the authors’ calculated change in storage plus recharge (solid line) for the SW region in their figure 1C; a conservation of mass calculation would produce a line through the center of mass of the reported 1981–2009 data. The calculated recharge values appear to have been adjusted in an unexplained manner. Given that, we also question the significance of the match obtained for the groundwater-supported corn plot in their figure 3A. The comparisons in their table S3 do little to substantiate the authors’ recharge estimates because of the above concerns and the lack of consistency with more recent process-based modeling investigations (3, 4). We conclude that this is an interesting, but highly flawed, mathematical exercise that has little bearing on future conditions in the High Plains Aquifer in western Kansas

Quantum oscillations of nitrogen atoms in uranium nitride

The vibrational excitations of crystalline solids corresponding to acoustic or optic one phonon modes appear as sharp features in measurements such as neutron spectroscopy. In contrast, many-phonon excitations generally produce a complicated, weak, and featureless response. Here we present time-of-flight neutron scattering measurements for the binary solid uranium nitride (UN), showing well-defined, equally-spaced, high energy vibrational modes in addition to the usual phonons. The spectrum is that of a single atom, isotropic quantum harmonic oscillator and characterizes independent motions of light nitrogen atoms, each found in an octahedral cage of heavy uranium atoms. This is an unexpected and beautiful experimental realization of one of the fundamental, exactly-solvable problems in quantum mechanics. There are also practical implications, as the oscillator modes must be accounted for in the design of generation IV nuclear reactors that plan to use UN as a fuel.Comment: 25 pages, 10 figures, submitted to Nature Communications, supplementary information adde

Low reproductive performance and high sow mortality in a pig breeding herd: a case study

Sow performance is a key component of the productivity of commercial pig farms. Reproductive failure in the sow is common in pig production. For every 100 sows served, 89 should farrow. In absence of specific diseases such as porcine parvovirus, pseudo-rabies, swine fever, leptospirosis and brucellosis, management failures are the most important causes of loss. A syndrome associated with reproductive inefficiency, and post-service vaginal discharge and high sow mortality in a commercial pig farm is described. Pregnancy failures exceeded 20% and sow mortality exceeded 12% for two consecutive years. The abnormal post-service vaginal discharge rate was 1.7% during the period of investigation