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The total syntheses of aflastatin A and its C3–C48 degradation fragment (6a, R = H) have been accomplished. The syntheses feature several complex diastereoselective fragment couplings, including a Felkin-selective trityl-catalyzed Mukaiyama aldol reaction, a chelate-controlled aldol reaction involving soft enolization with magnesium, and an anti-Felkin-selective boron-mediated oxygenated aldol reaction. Careful comparison of the spectroscopic data for the synthetic C3–C48 degradation fragment to that reported by the isolation group revealed a structural misassignment in the lactol region of the naturally derived degradation product. Ultimately, the data reported for the naturally derived aflastatin A C3–C48 degradation lactol (6a, R = H) were attributed to its derivative lactol trideuteriomethyl ether (6c, R = CD3). Additionally, the revised absolute configurations of six stereogenic centers (C8, C9, and C28–C31) were confirmed.

An emerging body of opinion cites the Daenerys subplot in George R. R. Martin’s A Song of Ice and Fire(1996–) as a white savior narrative. This article argues against this. Martin presents his emblematic medievalist Occident as equally barbaric as his Orient, disabling the Manichean colonialist allegory some scholars perceive in his work. Although Daenerys certainly thinks like a colonialist savior, such discourse makes most sense as Bakhtinian image of a language, exhibited by Martin in concert with depictions of the intractable problems her actions cause, to mount a polemic authorial critique of colonialist literature. Support for this reading can be found elsewhere in Martin’s work, in which he frequently critiques uncritical espousals of literary tropes, and in his careful moral variegation of the peoples Daenerys conquers.

The transition of dental ceramics and glass-ceramics (for fixed all-ceramics and metal-ceramics restorations and prostheses) from laboratory to clinic requires the materials to pass through a series of tests following the protocols and requirements discussed in the standard ISO 6872:2015. However, the literature reveals that the researchers in the dental ceramics community usually do not adhere to the ISO standard’s specifications when measuring their materials’ flexural strength, assuming that these deviations from the protocols exhibit minimal or no impact on the materials’ strength. Therefore, the present study aims to fill that gap by elucidating the impact of the following experimental protocols – (i) polishing, (ii) edge chamfering and (iii) adhesive tape on the non-tensile side – on three-point flexural strength of lithium disilicate based glass-ceramics. The result reveals that polishing increases flexural strength and tends to introduce edge or corner flaws in the specimen. Though edge chamfering of specimens did not help remove the edge defects in our study, it leads to a tighter flaw distribution, increasing the reliability of the flexural strength results. The application of adhesive tape (on the compressive side) exhibits an insignificant impact on the glass-ceramic specimens’ flexural strength. Accordingly, revisions have been suggested in the ISO 6872 standard.

Machine learning is a set of tools that are increasingly used in the field of chemistry. The introduction of potential uses of machine learning to undergraduate chemistry students should help to increase their comprehension of and interest in machine learning processes and can help support them in their transition into graduate research and industrial environments that use such tools. Herein we present an exercise aimed at introducing machine learning alongside improving students’ general Python coding abilities. The exercise aims to identify the regioisomerism of disubstituted benzene systems solely from infrared spectra, a simple and ubiquitous undergraduate technique. The exercise culminates in students collecting their own spectra of compounds with unknown regioisomerism and predicting the results, allowing them to take ownership of their results and creating a larger database of information to draw upon for machine learning in the future.

Over the past two decades, oral health has emerged as a health care priority. Historically, patients greater than 65 years of age, the economically disadvantaged, members of racial or ethnic minority groups, or the disabled or home bound have experienced significant barriers to routine dental care. The connection between oral health care and periprosthetic joint infections (PJI) continues to be of importance to the orthopedic surgeon, as such infections are significantly morbid and costly. This review aims to introduce the importance of oral health as a small but crucial portion of an arthroplasty patient's overall perioperative management.

Abstract:This article uses literary theory to propose an explanation for the range of responses to the art of Zdzisław Beksiński, whose work tends to provoke either hyperbolic disgust or intense awe. Beksiński's decision never to title his paintings necessitates ekphrasis, the translation of visual images into prose, which in the case of Beksiński's images breaks down due to the impossibility of describing his figures in plain speech. An ekphrasis of these images thus pushes the viewer into the second stage of Thomas Weiskel's three-stage model of Romantic transcendence—deprived of the ability to speak and searching for a way to recover it. Neither of Weiskel's codified approaches to this crisis—the metaphorical or the metonymical—are effective solutions to this problem, marooning viewers in Weiskel's second stage with no chance of reaching the third stage, where they would be reconciled with the contents of their world.The viewer of a Beksiński painting must therefore contend with what David Sandner calls an "open" response to the sublime, accepting the sublime as an ongoing feature of their world. One of Sandner's codified open responses, fragmentation, precisely describes the response of those who regard Beksiński's art as fearsome or disgusting, forcing the viewer into an encounter with something they dislike. The other, dispossession, closely describes the sense of transcendent power other viewers ascribe to these images. The process of Sandnerian dispossession with regard to Beksiński's paintings is elucidated by comparing it to a similar process in neo-Romantic theory, J. R. R. Tolkien's concept of Recovery, the highlighting of the natural and human via their contrast with purpose-built manifestations of the supernatural and inhuman. Various of Beksiński's paintings yield to such analysis, as studies of humanitas celebrated in contrast to preternatural inhumanity. The key to the power of these images is their ability to show the viewer something of themselves.

Turfgrasses benefit the environment through conversion of CO2into stable C stored in soils. Limited research on the sequestration potential of bermudagrass (Cynodonspp.) has been conducted in semiarid climates. The objective of this study was to evaluate soil physiochemical properties of golf courses in Lubbock, TX, to determine C sequestration potential and longevity. Soil was obtained from fairways of five golf courses ranging in age from 13 to 93 yr. Shallow (0–7.5 cm) and deeper (7.5–15 cm) soil depths were tested for soil pH, electrical conductivity, soil organic matter, soil organic C (SOC), inorganic C, total N, inorganic N, and texture. After ANOVA and mean separation, principal component analysis (PCA) was used to group golf courses by soil depth or age. Soil organic matter and SOC decreased with depth, but the rate of SOC accumulation (0.22 Mg C ha−1yr−1) was lower when compared with previous studies. Maximal C (35.1 and 23.7 Mg C ha−1in the upper and lower depths) was consistent with previous studies, indicating that C accumulated for a longer period of time. The PCA explained 52.7% of variability in soil physiochemical properties on two axes, but PCA more effectively differentiated soil sampling depth than golf course age. High variability in data among fairways at a single golf course likely resulted in limited grouping capabilities. Including a broader regional representation of golf courses or sampling golf courses between 40 and 70 yr to quantify soils near maximal accumulation would strengthen future studies.

High evapotranspirational demand combined with poor quality irrigation water increases salinity concerns in semiarid regions. Accumulated salts in the root zone may negatively affect bermudagrass (Cynodonspp.) growth and quality. The objective of this study was to examine the effectiveness of cultivation practices combined with products to enhance fairway conditions without applying leaching water levels. Two golf courses in Lubbock, TX, were selected for this research. Cultivation practices, including noncultivated control, core aerification, and slicing, were conducted in mid‐June of 2015 and 2016. Nine products recommended to enhance water movement or to disassociate sodium were applied within each cultivation treatment at label rates. Soil pH and electrical conductivity (EC) were determined from samples obtained in June, August, and October each year. Volumetric water content, visual turf quality, digital image analysis, normalized difference vegetation index, and ratio vegetation index were assessed from June to October in 2015 and 2016. Soil EC fluctuated with rainfall events. However, no treatment reduced soil EC. Gypsum‐based products increased soil EC but reduced pH at the conclusion of the research. Core aerification reduced aboveground parameters at Golf Course A because aerified holes remained visible throughout summer, whereas slicing and core aerification improved turf quality and ratio vegetation index at Golf Course B. These results emphasize the need to test irrigation water for the salinity hazard before implementing management strategies and the importance of leaching by rainfall or additional irrigation. Lastly, high surface disruption cultivation practices may inhibit bermudagrass recovery on higher clay content soils. Core IdeasRainfall and high ET fluctuated soil EC of bermudagrass golf fairways.Gypsum products increased soil EC and reduced soil pH after 2 yr of applications.Bermudagrass recovery from core aerification was slowed with higher clay content.Cultivation practices improved parameters on high sand content soil after recovery. Rainfall and high ET fluctuated soil EC of bermudagrass golf fairways. Gypsum products increased soil EC and reduced soil pH after 2 yr of applications. Bermudagrass recovery from core aerification was slowed with higher clay content. Cultivation practices improved parameters on high sand content soil after recovery.

Potato peel, a waste product of the potato processing industry, is high in bioactive compounds. We investigated the in vitro antitrichomonad activity of potato peel powders prepared from commercial Russet, red, purple, and fingerling varieties as well as several known potato components, alkaloids and phenolic compounds, against three pathogenic strains of trichomonads. Trichomonas vaginalisis a sexually transmitted protozoan parasite that causes the human disease trichomoniasis. Two distinct strains of the related Tritrichomonas fetusinfect cattle and cats. The glycoalkaloids α-chaconine and α-solanine were highly active against all parasite lines, while their common aglycone solanidine was only mildly inhibitory. α-Solanine was several times more active than α-chaconine. The phenolic compounds caffeic and chlorogenic acids and quercetin were mildly active against the parasites. Most of the potato peel samples were at least somewhat active against all three trichomonad species, but their activities were wide-ranging and did not correspond to their glycoalkaloid and phenolic content determined by HPLC. The two Russet samples were the most active against all three parasites. The purple potato peel sample was highly active against bovine and mostly inactive against feline trichomonads. None of the test substances were inhibitory toward several normal microflora species, suggesting the potential use of the peels for targeted therapeutic treatments against trichomonads.

Digital image analysis methods to evaluate putting green ball mark severity and recovery.Firmer surfaces from dry conditions or lightweight rolling increased maximum ball mark injury area.Rate of recovery was similar for all treatments, but increased wear increased time to 50% recovery.Demonstrates positive attributes of dispersing foot and equipment traffic throughout the green. Putting greens experience stress from golf balls striking the surface, maintenance equipment, and foot traffic. Improved creeping bentgrass (Agrostis stoloniferaL.) cultivars, sand‐based root zones, and skilled superintendents maintain plant health while providing firmer conditions. Many researchers have studied effects of compaction and wear on putting greens, but few have determined the effect of these stresses on ball marks. The objective of this research was to evaluate ball mark severity and recovery of creeping bentgrass under different mowing heights (2.5, 3.2, and 4.0 mm), rolling frequencies (0, 3, or 6 d wk−1), and foot traffic using digital image analysis. Digital images of golf balls placed in the depression were used to calculate ball mark depth, and a cover analysis was conducted to model ball mark injury area using a one phase decay model to determine theoretical maximum injury, slope, and days to 50% recovery. Soil moisture content was positively correlated with ball mark depth, but common stresses rarely altered ball mark depth. The mean theoretical maximum ball mark injury was 377 mm2greater for daily rolled treatments in 2010 compared to non‐rolled treatments. The slope of recovery rarely changed among treatments suggesting that theoretical maximum ball mark injury area has a greater effect on recovery. Lastly, combining the lowest mowing height or daily rolling and foot traffic slowed the time ball marks took to reach 50% recovery. This research demonstrates the effects common management practices and soil moisture have on the severity and recovery of ball marks during environmental stress.

The effects of recent climate change are accelerating permafrost thaw, including ice‐rich landscapes of the western Canadian Arctic. However, regional drivers of permafrost slope failure in hillslopes with warm, thin permafrost remain poorly understood. Repeat satellite imagery (1984–2020) indicates rapid increases in retrogressive thaw slumps (RTSs) and deep‐seated permafrost landslides (DSPLs) since 2004, indicating a change in slope stability thresholds in an area that otherwise appeared thaw stable. The widespread occurrence of DSPL represents a contrasting geomorphic response to the RTS‐dominated ice‐rich permafrost landscapes. In this study area, RTS and DSPL occur predominantly in areas that were burned by forest fires in the 1990s, indicating a legacy thermal disturbance that preconditioned permafrost hillslopes for failure. The relations between historic fires and the later development of widespread permafrost slope failures represent an outstanding example of the complex interactions between inherited landscape sensitivity in ice‐rich terrain and ongoing climate change. We characterize the type and nature of permafrost slope failures in the central Mackenzie Valley, NWT and find hillslope failures have increased rapidly over the past ∼15 years. This growth occurred in conjunction with increasing air temperatures and summer precipitation but the distribution of permafrost slope failures in this area is largely constrained by forest fire extents that affected the area in the 1990s. These fires have led to increased landscape sensitivity of this ice‐rich terrain through their impacts on ground temperatures. Recent increases in permafrost mass‐wasting frequency (278%) and magnitude (602%) reveal a permafrost landscape in geomorphic transitionMore than 80% of failures occur in areas burned in the 1990sCompounding effects of legacy thermal disturbance and climate drivers of thaw likely to increase slope instability of warm permafrost Recent increases in permafrost mass‐wasting frequency (278%) and magnitude (602%) reveal a permafrost landscape in geomorphic transition More than 80% of failures occur in areas burned in the 1990s Compounding effects of legacy thermal disturbance and climate drivers of thaw likely to increase slope instability of warm permafrost

Dual-energy CT can distinguish intraparenchymal hemorrhage from calcification rapidly and with very high accuracy in emergency department patients and can be especially useful in problem-solving complex cases that are difficult to interpret based on conventional CT findings.

Creeping bentgrass (Agrostis stoloniferaL.) putting greens in the transition zone experience high levels of environmental stress during summer months. The interaction of common management practices combined with foot traffic can exacerbate environmental stress. The objective of this study was to determine the effect of management practices combined with foot traffic during high environmental stress in the transition zone. Creeping bentgrass cultivars, SR 1020 and Penn G2, were managed with various mowing heights (2.5, 3.2, or 4.0 mm), rolling frequencies (0, 3, or 6 d per week), and foot traffic. As environmental stress became prominent during summer months, bentgrass maintained at the lowest mowing heights exhibited poorer turf quality, coverage, and wear tolerance compared to the highest mowing height. SR 1020 quality was reduced below acceptable levels in July when mowed at the lowest mowing height in 2011 and 2012. Penn G2 maintained acceptable quality at all mowing heights in 2011, but severe heat and drought stress reduced turf quality regardless of mowing height in 2012. Daily rolling significantly increased wear on both cultivars during high environmental stress that resulted in decreased turf quality and coverage compared to the non‐rolled treatments. The combination of wear from mechanical stress and foot traffic increased wear injury on both cultivars. Under reduced daylengths and optimal air temperatures in September of each year, all response variables improved to similar levels.

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Relatively little is known about how liposomal formulations modulate drug delivery to fungal pathogens. We compared patterns of hyphal cell wall binding for empty rhodmine-labeled liposomes and the clinically available amphotericin B-containing liposomal formulation (AmBisome) in Aspergillus fumigatusand Candida albicans.Following 0.5 h of coincubation with A. fumigatus, empty liposomes concentrated primarily in fungal septae along at the surface of the cell wall, suggesting that liposome uptake is concentrated in areas of the cell wall where linear glucan is exposed on the cell surface, which was confirmed by aniline blue staining. Consistent with this hypothesis, pretreatment of liposomes with soluble linear glucan (laminarin) decreased liposome binding in both Aspergillusand Candidafungal hyphae, while growth of Aspergillushyphae in the presence of an agent that increases fungal cell wall surface exposure of linear β-glucans without cell death (caspofungin) increased liposome uptake throughout the Aspergillusfungal cell wall. Increasing the polyethylene glycol (PEG) concentration in liposomes from 0 to 30% significantly increased fungal uptake of liposomes that was only modestly attenuated when fungal cells were incubated in serum concentrations ranging from 10 to 100%. The presence of β-glucans on the fungal hyphae cell walls of Aspergillus fumigatusis one of the factors responsible for mediating the binding of liposome carriers to the hyphae and could explain possible synergy reported between liposomal amphotericin B and echinocanins.

Standard cavography is performed with iodinated contrast material with plain film or digital subtraction technique. However, preplacement imaging may change final inferior vena cava filter (IVC) placement in 11 to 26% of patients. This study will examine the use and reliability of incidental spiral computed abdominal tomography (CAT) scans for the placement of IVC filters.

Few data exist in regard to long-term and functional outcome after ruptured abdominal aortic aneurysm (rAAA) repair. The present study provides such follow-up and defines the impact of variables used to grade resuscitation efforts [base deficit (BD) and core temperature (cT)]. One hundred forty-seven patients presenting with rAAA were retrospectively reviewed. Overall perioperative mortality was 35 per cent (51/147) and mean age was 72 years. Survival data were available for 99 per cent of patients with a mean and median follow-up of 45 months. Life table analysis revealed one-, 2-, and 5-year survival to be 81, 75, and 58 per cent, respectively. Eighty-three per cent of patients reported a quality of life equal to that of their preoperative status. Both initial cT (P= 0.02) and BD (P= 0.03) were significantly associated with perioperative mortality. Using a logistic regression model cT remained a significant factor (P= 0.006) associated with survival. Smoking, hypertension, diabetes, chronic obstructive pulmonary disease, mode of transportation, and surgeon's training were not significant. Despite the advanced age of the present cohort, acceptable perioperative mortality and long-term survival rates were attained. The majority of patients resumed a lifestyle comparable to that of their preoperative state; therefore, long-term longitudinal follow-up suggests that aggressive management with rapid correction of BD and cT results in excellent functional outcome.

There is considerable controversy regarding the existence of celiac axis compression syndrome. Despite this, there is clearly a subset of patients with extrinsic compression of the celiac axis who have symptoms and who benefit from operative therapy. Clinical features that may help to identify those patients who are most likely to respond to surgical therapy have been studied; however, the authors present a patient who had a favorable surgical outcome despite lacking many of these clinical features. The patient had significant celiac steal. They suspect that the presence of celiac steal may be an important determinant of a successful surgical outcome.

These writers suggest a number of ways principals can help teachers to reduce stress, and thus avoid burnout. The same tech niques, of course, will work for ad ministrators them selves.

The educator who deals effectively with student misbehavior is probably focusing on the causes of that behavior, these authors believe. A process designed to promote understanding of student motivation, andto help in dealing effectively with misbehavior, is outlined in this article.

Outlined here is a management process designed for use by educators in resolving conflict situations. The process has been utilized successfully in a wide range of problem situations.

Over a 1-year period, three patients were seen in our trauma service with delayed bleeding (≥7 days) from an initially inapparent splenic injury. This entity was defined as a late occurrence of signs and symptoms attributed to splenic injury not detected by diagnostic computed tomographic (CT) scanning during the initial examination. We believe that this represents an “Injury in evolution” minor enough to go undetected on initial CT scans of the abdomen. A high index of suspicion and liberal utilization of imaging techniques are essential for the identification of delayed splenic rupture. Further multicenter studies are required to delineate the true incidence of its occurrence and its clinical significance. We conclude that “delayed rupture” of the spleen is a true clinical entity. The occurrence of a delayed rupture may prove hazardous to patients discharged early from the hospital after blunt abdominal injury. A classification system to assess this type of injury is suggested.