There is an urgent need to develop agricultural methods that balance water supply and demand while at the same time improve resilience to climate variability. A promising instrument to address this ...need is biochar – a charcoal made from pyrolyzed organic material. However, it is often unclear how, if at all, biochar improves soil water availability, plant water consumption rates and crop yields. To address this question, we synthesized literature-derived observational data and evaluated the effects of biochar on evapotranspiration using a minimal soil water balance model. Results from the model were interpreted in the Budyko framework to assess how climatic conditions mediate the impacts of biochar on water fluxes. Our analysis of literature-derived observational data showed that while biochar addition generally increases the soil water holding capacity, it can have variable impacts on soil water retention relative to control conditions. Our modelling demonstrated that biochar increases long-term evapotranspiration rates, and therefore plant water availability, by increasing soil water retention capacity – especially in water-limited regions. Biochar amendments generally increased crop yields (75% of the compiled studies) and, in several cases (35% of the compiled studies), biochar amendments simultaneously increased crop yield and water use efficiencies. Hence, while biochar amendments are promising, the potential for variable impact highlights the need for targeted research on how biochar affects the soil-plant-water cycle.
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•Data synthesis shows biochar generally increases soil water retention capacity.•In some cases, biochar improved both crop yields and water use efficiencies.•Modelling found biochar to consistently increase ET rates, mainly in water limited regions.•Biochar may boost agricultural yield and resilience to variability of rainfall.•Theory-practice gap of biochar effects on soil water: integrative research needed.
Soil heterogeneity influences microbial access to substrates and creates habitats varying in substrate concentrations, thus leading to local variations in carbon (C) dynamics. Based on theoretical ...considerations, we expected that higher heterogeneity would decrease microbial activity. To test this hypothesis, we modified substrate spatial heterogeneity using 3D-printed cylinders with four compartments (either preventing or allowing diffusion between compartments). The same total amount of glucose (1.5 mg glucose C per cylinder) was added either to one compartment (highest local concentration, 2.0 mg glucose C g−1 soil, and highest heterogeneity), to two (medium concentration, 1.0 mg glucose C g−1 soil, and intermediate heterogeneity), or to four compartments (lowest local concentration, 0.5 mg glucose C g−1 soil, and equivalent to homogeneous conditions). Thus, we experimentally created a gradient of substrate spatial heterogeneity. The 3D cylinders containing soil were transferred into standard calorimetry ampoules and were incubated in isothermal calorimeters to monitor soil heat dissipation rates as a proxy of soil microbial activity over 51 h at 18 °C. When diffusion among compartments was prevented, the most heterogeneous treatment showed the lowest heat dissipation rates, despite having the highest local substrate concentration. Compared to homogeneous conditions, the heat dissipation rate from the most heterogeneous treatment was 110% lower at the beginning of the experiment (12.7 μJ g−1 soil s−1) and 50% lower when heat dissipation rates reached a peak (72.6 μJ g−1 soil s−1). Moreover, the peak was delayed by approximately 2 h compared to the most homogeneous treatment. When diffusion among compartments was allowed, the effect of substrate spatial heterogeneity on microbial activity was strongly diminished. Our findings emphasize the influence of substrate spatial heterogeneity on soil microbial dynamics, highlighting the importance of including it in C cycling models for a better understanding of soil C dynamics.
•A gradient of substrate spatial heterogeneity is created experimentally.•Increasing degree of heterogeneity decreases microbial activity.•Allowing substrate to diffuse diminishes the effect of heterogeneity.•Effect of heterogeneity is explained by scale transition theory in C cycling model.•Substrate spatial heterogeneity provides evidence for the delay in C decomposition.
Central Intelligence Agency (CIA) lore and popular culture tout Col. Oleg Penkovsky as "the spy who saved the world" during the Berlin and Cuban missile crises. In fact, his contribution to U.S. ...intelligence and policymaking is exaggerated, distorted, and in several instances falsified. More disturbing, Penkovsky harbored a murderous rage against the Soviet system and repeatedly tried to inveigle the West in a quixotic quest to destroy it. He devised a plan to blow up Moscow, advocated preventive war against the Soviet Union, fanned the flames of the Berlin crisis with false reports of Kremlin mobilization for war, and recommended assassinating Soviet leader Nikita Khrushchev. Penkovsky allegedly provided critical information that bought time for President John F. Kennedy to devise a diplomatic solution to the Cuban crisis before Soviet missiles were ready to fire. Not true, according to the president's advisers. New information reveals that some Soviet missiles were combat-ready two days before U.S. intelligence discovered the first incomplete launch site. The State Committee for Security (KGB) allowed Penkovsky to continue spying for at least ten months after he came under suspicion, perhaps to protect a mole in American or British intelligence. A senior CIA officer claimed that, meanwhile, the Soviets controlled and manipulated Penkovsky without his knowledge. Even after his arrest, Penkovsky may have attempted to instigate a nuclear war by tricking the KGB into sending a false alert of an impending Soviet surprise attack on the United States.
Catchments consist of distinct landforms that affect the storage and release of subsurface water. Certain landforms may be the main contributors to streamflow during extended dry periods, and these ...may vary for different catchments in a given region. We present a unique dataset from snapshot field campaigns during low‐flow conditions in 11 catchments across Switzerland to illustrate this. The catchments differed in size (10 to 110 km2), varied from predominantly agricultural lowlands to Alpine areas, and covered a range of physical characteristics. During each snapshot campaign, we jointly measured streamflow and collected water samples for the analysis of major ions and stable water isotopes. For every sampling location (basin), we determined several landscape characteristics from national geo‐datasets, including drainage area, elevation, slope, flowpath length, dominant land use, and geological and geomorphological characteristics, such as the lithology and fraction of quaternary deposits. The results demonstrate very large spatial variability in specific low‐flow discharge and water chemistry: Neighboring sampling locations could differ significantly in their specific discharge, isotopic composition, and ion concentrations, indicating that different sources contribute to streamflow during extended dry periods. However, none of the landscape characteristics that we analysed could explain the spatial variability in specific discharge or streamwater chemistry in multiple catchments. This suggests that local features determine the spatial differences in discharge and water chemistry during low‐flow conditions and that this variability cannot be assessed a priori from available geodata and statistical relations to landscape characteristics. The results furthermore suggest that measurements at the catchment outlet during low‐flow conditions do not reflect the heterogeneity of the different source areas in the catchment that contribute to streamflow.
Our study highlights the high spatial variability of discharge and streamwater chemistry during low flow periods. We assessed whether this variability could be explained by catchment properties like topography, land use and geology and found that these correlations were catchment specific and differ in strength and direction. Measurements at the catchments outlets do not reveal the patchiness and large heterogeneity of discharge and stream water chemistry within headwaters. Targeted snapshot campaigns can reveal this information.
To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations.
...The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped (60)Co heads. The unit is supported by a Monte Carlo-based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient at the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system.
The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26 minutes.
Online adaptive MR-IGRT has been successfully implemented with planning and QA workflow suitable for routine clinical application. Clinical trials are in development to formally evaluate adaptive treatments for a variety of disease sites.
SpaceOAR, a Food and Drug Administration–approved hydrogel intended to create a rectal–prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation ...therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years.
Cumulative (Common Terminology Criteria for Adverse Events, version 4.0) toxicity was evaluated using the log-rank test. Quality of life (QOL) was examined using the Expanded Prostate Cancer Index Composite (EPIC), and the mean changes from baseline in the EPIC domains were tested using repeated measures models. The proportions of men with minimally important differences (MIDs) in each domain were tested using repeated measures logistic models with prespecified thresholds.
The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P<.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P<.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02).
The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in prostate radiation therapy.
My Two Moles: A Memoir Fischer, Benjamin B.
International journal of intelligence and counterintelligence,
01/2022, Letnik:
35, Številka:
1
Journal Article
Recenzirano
Fischer shares his experience during his stint in the intelligence community. He mentions "During my career, I had the dubious experience of crossing paths with the two most notorious foreign ...intelligence penetrations ("moles") of the U.S. Intelligence Community (IC) during and after the Cold War: Central Intelligence Agency (CIA) officer Aldrich (Rick) Ames and Federal Bureau of Investigation (FBI) agent Robert Hanssen. My association with Ames was up close but not personal. I occupied a cubicle next to his in the CIA's Counterintelligence Center (CIC). Rick was a loner, and I cannot recall a single conversation we might have had. But I could not help overhearing his phone conversations through the thin partitions that separated us. Some of what I heard seemed insignificant at the time but acquired new meaning after his arrest. I never met Hanssen. Our connection, as it were, was spectral but still unsettling. The rogue G-man stole thousands of classified documents, and one was a product of my own labors. I had completely forgotten about it until I picked up a book about his espionage career. Lo and behold, there it was, cited in a footnote that listed CIA documents Hanssen had purloined."
COVID-19 caused many disruptions, not only in society, but also in university education, including in hydrology and water-related sciences. Taking part in
an academic teaching training course at ...Uppsala University during COVID-19, we got curious about how COVID-19 might have impacted European water
education. Consequently, we chose to investigate this aspect in the
mandatory project of the course by conducting an online survey. In this
paper, we communicate the results of the survey and reflect (hold up a
mirror to water education) on how the teaching of hydrology and
water-related sciences changed due to COVID-19. The answers of 28
respondents, working in the field of hydrology at different universities across Europe, showed that in the pre-COVID-19 classroom lectures,
laboratory work and fieldwork were commonly used teaching formats in courses with 10 to more than 40 students. These results agreed with those found in the literature. The occurrence of COVID-19 forced hydrological education to suddenly move from classroom to online teaching, which was possible thanks
to the available digital tools and technical infrastructure. The practiced
online teaching format remained lectures. Most of the respondents
(>40 %) reported not using classroom assessment techniques to
gauge the students' performances. In addition, a loss of human interaction
in the online environment was noticeable. Hence, whether students reached
their learning outcomes during distance teaching was largely unknown. The most affected learning activities were the ones that could not be moved to online
teaching, such as laboratory work and fieldwork. As a result, comprehensive hydrological knowledge might be missing for at least several cohorts of
hydrologists. In this way, COVID-19 caused a secondary effect on society
which needs skills in solving future challenges such as water management in a changing climate. Next to negative aspects, we observed positive COVID-19 aspects;
for example, the hydrology community explored novel teaching formats and shared teaching material and experiences online. COVID-19 forced hydrology teachers to explore, improvise, and be creative to continue teaching. Hydrology can use this experience to learn from and modernize hydrology education by
developing a lesson design suited for the online environment, including best
practices and making practical and “exotic” non-traditional teaching formats accessible to all hydrology and water students.
An emergent technique of patterning surfaces with solid particles utilizes the evaporation of colloidal droplets from a substrate. Upon complete evaporation of the liquid, the suspended particles ...remain adhered to the solid in a variety of patterns. Experimentally, the type of particle deposit has been correlated with the mode of liquid evaporation. It is expected that the manner in which the liquid evaporates from the droplet should significantly affect the flow of fluid inside the droplet. Therefore, the determination of the flow profiles in the droplet will aid in understanding the redistribution of particles under different experimental conditions. Using lubrication theory, this study shows that either an outward flow toward the contact line or an inward flow toward the center of the droplet can be induced, depending on the evaporative driving force. If an outward flow toward the contact line is generated inside the droplet, then a ringlike deposit remains on the substrate. Conversely, if the liquid inside the droplet flows away from the contact line, then a more uniform solute deposit will adhere to the solid.
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