cssi/SciSciGPT-SciSciNet huggingface dataset:
Mass spectral study of ring E of taraxasterol and compounds with similar ring substitution

The origin of the [M–69]+ and [M–111]+ signals in the mass spectrum of taraxasterol was studied through the use of C(18), (19), (21), (22) and/or (30) deuteriated derivatives. The generality of these signals for ring systems with an exocyclic methylene group and a methyl moiety on an adjacent carbon was verified with 2-methylmethylenecyclohexane, 1-methyl-2-methylene-trans-decalin, 1,10-dimethyl-2-methylene-trans-decalin and some of their deuteriated derivatives. The most plausible mechanism for the formation of the [M–69]+ ion appears to involve cleavage of both bonds allylic to the exocyclic methylene group with a 1,3-hydrogen transfer from the adjacent ring. Genesis of the [M–111]+ ion is more complicated but a five-membered allylic ion generated from ring D is proposed.
Racial Disparities in HIV and Liver Disease

Based on the recent Center of Disease Control (CDC) report, an estimated 1.1 million persons in the USA are infected with the human immunodeficiency virus (HIV). Several US-based population studies have consistently shown a significant ethnic variation in HIV prevalence, with ethnic minorities accounting for about 70% of those living with HIV. In 1997, for the purposes of federal statistics reporting, the Office of Management and Budget revised the classification of individuals by race and ethnicity. The revision identified five racial and two ethnic groups. The racial categories are as follows: (1) White, (2) Black or African American, (3) Asian, (4) Native Hawaiian or other Pacific Islander, and (5) American Indian or Alaskan Native; the ethnic categories are as follows: (1) Hispanic or Latino and (2) non-Hispanic/Latino. Owing to the lack of consistency in the classification across published studies, in this review ethnicity and race are used interchangeably. Ethnicity/race will be categorized as (1) White or Caucasian, (2) Black or African American, (3) Hispanic or Latino, (4) Asian, and (5) others.
Reassembly of Corneal Epithelial Adhesion Structures After Excimer Laser Keratectomy in Humans

Objective: To determine the pattern of long-term reformation of the adhesion structures after excimer laser phototherapeutic keratectomy. Methods: Four corneal buttons were removed at penetrating keratoplasty 6 to 15 months after initial excimer laser phototherapeutic keratectomy. Morphometric analysis of electron micrographs of the wound bed was performed to determine the extent and pattern of reformation of hemidesmosomes, anchoring fibrils, and basal laminae. Results: Eight percent of the basal epithelial cells had underlying normal anchoring fibrils at 6 months, compared with 35% at 15 months. The percentage of basal cell membrane occupied by hemidesmosomes remained fairly constant (35.2% to 37.7%). With the exception of a localized area of multilamination seen at 9 months, the cross-sectional area of basal lamina per 100 μm of basal cell membrane increased with the duration of wound healing (18.0 μm 2 at 6 months, 24.4 μm 2 at 15 months) but remained below normal levels (32 μm 2 ). Conclusions: These data suggest that after human excimer keratectomy, the anchoring fibrils and basal lamina do not completely normalize even after 15 months.
Superoxide Dismutase as a Tool for the Mulacular Identification of Plant Parasitic Nematodes.

Superoxide dismutase (SOD) is a constitutive family of enzymes produced by all aerobic organisms. Varying amounts of SOD activity have been found at all life stages of the most diffused plant parasitic nematodes. SOD is important to aerobic metabolism and parasitism of nematodes in that it catalyzes the first step of the neutralization of the highly toxic superoxide anion (O2 •-), which is largely produced in plant-nematode incompatible reactions. SOD has also been shown to be a significant tool to diagnose root-knot, cyst-, and longidorid nematodes. A high SOD polymorphism has been revealed by Native-Page on gradient polyacrylamide gels for Meloidogyne spp. and by isoelectrofocusing for Globodera, Xiphinema and Longidorus spp. The sensitivity of such procedures has been improved by using the PhastSystem (Amersham Biosciences, Piscata, NJ, USA), an automated equipment for electrophoresis. An accurate discrimination of species of all the nematode genera tested has been achieved and an attempt was made to group populations of the Xiphinema americanum-group and to detect Globodera rostochiensis and G. pallida pathotypes.
Temperature dependence of dimerization and dewetting of large-scale hydrophobes: a molecular dynamics study.

We studied by molecular dynamics simulations the temperature dependence of hydrophobic association and drying transition of large-scale solutes. Similar to the behavior of small solutes, we found the association process to be characterized by a large negative heat capacity change. The origin of this large change in heat capacity is the high fragility of hydrogen bonds between water molecules at the interface with hydrophobic solutes; an increase in temperature breaks more hydrogen bonds at the interface than in the bulk. With increasing temperature, both entropy and enthalpy changes for association strongly decrease, while the change in free energy weakly varies, exhibiting a small minimum at high temperatures. At around T = Ts = 360 K, the change in entropy is zero, a behavior similar to the solvation of small nonpolar solutes. Unexpectedly, we find that at Ts, there is still a substantial orientational ordering of the interfacial water molecules relative to the bulk. Nevertheless, at this point, the cha...
The Developing Genome: An Introduction to Behavioral Epigenetics

Part I: What's the Big Deal? Getting Up to Speed 1. Context 2. Phenotypes 3. Development 4. DNA 5. Zooming in on DNA 6. Regulation 7. Zooming in on Regulation Part II: What Do We Know? 8. Epigenetics 9. Zooming in on Epigenetics 10. Experience 11. Zooming in on Experience 12. Primates 13. Memory 14. Zooming in on Memory 15. Nutrition 16. Zooming in on Nutrition Part III: The Meanings and Mechanics of Inheritance 17. Inheritance 18. Multiplicity 19. Evidence 20. Grandparents Part IV: Implications 21. Caution 22. Hope 23. Conclusions Acknowledgments Notes References Index
Environmental ratings and children's social behavior: implications for the assessment of day care quality

Social interactions of four-year-olds in proprietary day care centers with high and low environmental ratings were compared. No clear-cut association between the ratings and social behavior was found. Alternative explanations for the complex pattern of results are suggested, and implications for the assessment of day care quality are offered.
Allogeneic hematopoietic cell transplant for peripheral T-cell non-Hodgkin lymphoma results in long-term disease control.

The study analyzed outcomes of a consecutive case series of 37 patients with peripheral T-cell non-Hodgkin lymphoma, from related and unrelated donors, using allogeneic hematopoietic cell transplant (allo-HCT), between the years 2000 and 2007. All patients were pretreated; the majority had either relapsed or progressive disease (n = 25, 68%), 13 had cutaneous histologies (CTCL), and all were ineligible for autologous transplant. Fully ablative conditioning regimens were used in 13 patients while 24 patients underwent reduced intensity conditioning (RIC). At 5 years the overall survival (OS) and progression-free survival (PFS) probabilities were 52.2% and 46.5%, respectively. At the time of analysis, nine (24.3%) patients had either relapsed (n = 6) or progressed (n = 3) post allo-HCT. The cumulative incidences of relapse/progression and non-relapse mortality at 5 years were 24.3% and 28.9%. No statistically significant variables for survival or relapse were discovered by univariate Cox regression analysis...
Low-Profile, Highly-Selective, Dual-Band Frequency Selective Surfaces With Closely Spaced Bands of Operation

We present a new design of a dual-band frequency selective surface (FSS) with closely spaced bands of operation and a highly-selective frequency response at each band. A multi-stage design procedure is also proposed for the design and synthesis of this class of frequency selective surfaces. The design procedure is based on synthesizing the desired device from its equivalent circuit parameter values. An approximate analytical technique is provided, which can be used to determine the values of the equivalent circuit parameters of this dual-band device from the basic system level characteristics of its transfer function including the center frequencies of operations of its two bands of operation and the bandwidth at each of these bands. The use of this design procedure is described in detail by a design example which follows the proposed design procedure step by step; the validity of the procedure is verified using full-wave EM simulations and experimental characterization of a fabricated prototype of the proposed device. Experimental characterizations of this device show that it has a stable frequency response as a function of angle of incidence for both the transverse electric (TE) and the transverse magnetic (TM) polarizations. This stability is attributed to the extremely small overall thickness of the structure as well as its small unit cell dimensions.
Linear pre/post filters for DCT-based image coding systems

We propose a novel method for designing linear, space- invariant pre/post filters for DCT-based image coders that minimize the mean square error. We use a linear gain-plus-additive noise model to describe the effects of a class of entropy-coded uniform threshold quantizers. Using this quantizer model and a homoge- neous random field model for the input source, we derive an explicit expression for the power spectral density of the reconstruction error in an improved transform coding system that includes pre/post fil- ters. Linear pre/post filters are subsequently designed that minimize the overall mean square error for a given input source and target rate. The postfilter coefficients are designed at the transmitter, and are sent to the receiver as part of the coded data. Such pre/post filters improve the frequency domain behavior of the system, when coding random fields. However, when coding natural images, one must account for spatial errors as well, such as blocking artifacts. We therefore develop an a posteriori method of designing linear postfilters that uses the actual image data and maximizes the PSNR performance of the system. We present simulation results that show that pre/post filters can help DCT-based coders to match the perfor- mance of subband/wavelet coders. We design short, adaptive, lin- ear postfilters for the Baseline JPEG coder that surpass the PSNR performance of other post-processing methods described in the lit- erature. © 1998 SPIE and IS&T. (S1017-9909(98)00103-2)
Developmental Expression Patterns of GABAA Receptor Subunits in Layer 3 and 5 Pyramidal Cells of Monkey Prefrontal Cortex

Cortical pyramidal neuron activity is regulated in part through inhibitory inputs mediated by GABAA receptors. The subunit composition of these receptors confers distinct functional properties. Thus, developmental shifts in subunit expression will likely influence the characteristics of pyramidal cell firing and the functional maturation of processes that depend on these neurons. We used laser microdissection and PCR to quantify postnatal developmental changes in the expression of GABAA receptor subunits (α1, α2, α5, β2, γ2, and δ) in layer 3 pyramidal cells of monkey prefrontal cortex, which are critical for working memory. To determine the specificity of these changes, we examined glutamate receptor subunits (AMPA Glur1 and NMDA Grin1) and conducted the same analyses in layer 5 pyramidal cells. Expression of GABAA receptor subunit mRNAs changed substantially, whereas glutamate receptor subunit changes were modest over postnatal development. Some transcripts (e.g., GABAA α1) progressively increased from birth until adulthood, whereas others (e.g., GABAA α2) declined with age. Changes in some transcripts were present in only one layer (e.g., GABAA δ). The development of GABAA receptor subunit expression in primate prefrontal pyramidal neurons is protracted and subunit- and layer-specific. These trajectories might contribute to the molecular basis for the maturation of working memory.
PROPHETS AND LOSSES: REASSESSING THE RETURNS TO ANALYSTS' STOCK RECOMMENDATIONS

Brad BarberGraduate School of ManagementUniversity of California, Davise-mail: bmbarber@ucdavis.eduReuven LehavyHaas School of BusinessUniversity of California, Berkeleye-mail: lehavy@haas.berkeley.eduMaureen McNicholsGraduate School of BusinessStanford Universitye-mail: fmcnich@leland.stanford.eduandBrett TruemanHaas School of BusinessUniversity of California, Berkeleye-mail: trueman@haas.berkeley.eduMay 2001
Dual Mobility for Chronic Instability: Solution Option

The purpose of this paper is to: (1) define the concept of a dual mobility acetabular component; (2) present the clinical issue that a dual mobility cup seeks to address; and (3) review the clinical and laboratory data available on dual mobility acetabular components.
Otto warburg: “on the origin of cancer cells”

0 N FEB. 24, 1956, there appeared in Science, the weekly publication of the American Association for the Advancement of Science, a translation from the German of an article by Dr. Otto Warburg’ entitled “On the Origin of Cancer Cells. ” Biochemists are agreed that, while this is a controversial article, it will remain a lasting and extremely valuable contribution to cancer biochemistry. It scparatcs much of the wheat from the chaff of cancer rcsearch, and focuses in unequivocal fashion on distinct and fundamental metabolic differences between cancer and noncancer cells. It,s central theme was developed thirty years ago; the data upon which the theme is based are unassailable. This group, perhaps more than many others in dentistry, works intimately with the cancer problem. The sense of fut,ility and lack of understanding which has continually been with workers in t,his field is slowly lifting and is being rcplaccd by an expectancy that this problem may be solved in the forseeable future. For this reason, it has been decided to review with you the article entitled ‘(On the Origin of Cancer Cells.” We will note, in so doing. how it. is within dentistry’s power to contribut,e grratly to a solution of the cancer problem. First, let us consider Warburg’s own summary of his researches (covering literally thousands of carefully planned and executed experiments) carried out during a thirty-year period ; then we can discuss in some detail the concepts involved.
Thermal stress simulation and chemical compatibility of glass composite seals with YSZ for solid oxide fuel cells

Summary The selection of the components is important for the solid oxide fuel cells (SOFC) in order to address the sealing issues. In the present investigation, the glass composite seals have been prepared by mixing the different glass compositions in fixed ratio and then ball milling for 5 h without using any unreactive particle in glass matrix. The chemical compatibility of the prepared glass composites with the solid electrolyte yttria stabilized zirconia (YSZ) has been studied using the scanning electron microscope (SEM) and dot-mapping techniques. The interfacial study has revealed that all the glass composites except GG5 have shown good adhesion along with no undesired chemical reaction at the interfaces. Furthermore, the thermal stress generated within the glass composite/YSZ diffusion couple has been simulated for 10 000 h heat-treatment at 800 °C along with its magnitude using the COMSOL multiphysics analysis. Interestingly, for all the diffusion couples, the stress is within the acceptable limit, but for the GG5 composite/YSZ couple, the stress varies between 6 and 529 N/m2. In addition to this, for the GG5 composite/YSZ couple, the interface exhibits a high stress zone, which shows good correlation with the microstructural analysis. Copyright © 2015 John Wiley & Sons, Ltd.
Prediction Policy Problems.

Empirical policy research often focuses on causal inference. Since policy choices seem to depend on understanding the counterfactual–what happens with and without a policy–this tight link of causality and policy seems natural. While this link holds in many cases, we argue that there are also many policy applications where causal inference is not central, or even necessary. Consider two toy examples. One policy maker facing a drought must decide whether to invest in a rain dance to increase the chance of rain. Another seeing clouds must deciding whether to take an umbrella to work to avoid getting wet on the way home? Both decisions could benefit from an empirical duty of rain. But each has different requirements of the estimator. One requires causality: do rain dances cause rain? The other does not, needing only prediction: is the chance of rain high enough to merit an umbrella? We often focus on rain dance like policy problems. But there are many important policy problems umbrella-like. Not only are these prediction problems neglected, machine learning can help us solve them more effectively. In this paper, we (i) provide a simple framework that clarifies the distinction between causation and prediction; (ii) explain how machine learning adds value over traditional regression approaches in solving prediction problems; (iii) provide an empirical example from health policy to illustrate how improved predictions can generate large social impact; (iv) illustrate how “umbrella” problems are common and important in many important policy domains; and (v) argue that solving these problems produces not just policy impact but also theoretical and economic insights.1
One But Not the Only: Reconfiguring Intimacy in Multiple Partner Relationships

The romantic love ideology that permeates our culture, shapes marriages, and structures perceptions of what love should be frames the ideal intimate relationship as a (heterosexual) bond in which “one and only soulmates” share an intense emotional closeness and sexual attraction in committed monogamy. In this framework, sexual fidelity and exclusivity serve as markers of shared trust and uniqueness, making these facets of idealized romantic love perhaps the most central and important defining characteristics of such relationships. Multiple partner intimacies can thus pose significant challenges to relationships and notions of romantic love. Drawing on in-depth interviews with 55 people who are either in mixed orientation marriages or polyamorous relationships, this study examines how couples negotiate marital situations in which one or both spouses have extramarital lovers. These negotiations reveal how and why some participants could reconfigure aspects of romantic love so that being the “one” no longer required being the “only.” These reconfigurations highlight the links between the romantic love ideology and traditional gendered power dynamics, illustrating how multiple partner intimacies may have the potential to challenge hegemonic gender and sexual ideals.
My Rememberance of gas Chromatography

The story presented here covers the early history of gas chromatography from 1950 to 1965. A blend of scientific and commercial developments are intertwined as seen from my perspective. Thus, the title “My Rememberance of Gas Chromatography”.
Radiographic Kinetics of Sarcomatoid Renal Cell Carcinoma

Renal cell carcinoma is a common entity often managed surgically with excellent survival benefits. We report a rare case of sarcomatoid renal cell carcinoma with aggressive growth kinetics after palliative resection captured radiographically.
Conformational Stability from Variable Temperature Infrared Spectra of Xenon Solutions, r0 Structural Parameters, and Ab Initio Calculations of Cyclopropylisocyanate

Infrared spectra (4000 to 400 cm−1) of the gas and variable temperature xenon solutions, and the Raman spectrum of the liquid have been recorded for cyclopropylisocyanate. The enthalpy difference has been determined to be 77 ± 8 cm−1 (0.92 ± 0.10 kJ/mol) with the trans form more stable than the cis conformer with 59 ± 2% present at ambient temperature. By utilizing three rotational constants for each conformer, combined with structural parameters predicted from MP2(full)/6-311+G(d,p) calculations, the adjusted r0 parameters have been obtained. Heavy atom structural parameters for the trans [cis] conformers are the following: distances (A) (C−C2,3) = 1.509(3) [1.509(3)], (C2−C3) = 1.523(3) [1.521(3)], (C−N) = 1.412(3) [1.411(3)], (N═C) =1.214(3) [1.212(3)], (C═O) = 1.163(3) [1.164(3)]; angles (°) ∠CCN = 116.7(5) [120.1(5)], ∠CNC = 136.3(5) [137.6(5)]. The centrifugal distortion constants have been predicted from ab initio and DFT calculations and are compared to the experimentally determined values.
Atheroprotective potential of CXCR4 on B1 cells (CAM4P.145)

Atherosclerosis is a chronic inflammatory condition in which lipid deposition in arteries leads to the recruitment, activation, and accumulation of immune cells in the artery wall. Immune cells can have protective or detrimental effects on disease development. Existing evidence demonstrates that B1 cells hinder atherosclerotic lesion formation by secreting natural IgM antibodies that recognize modified self-epitopes present in diseased arteries. However, the mechanisms underlying B1 cell migration to arteries require further study. Our lab utilizes flow cytometry of circulating human immune cells in patients undergoing intravascular ultrasound of coronary arteries, in order to identify key surface markers that are associated with plaque burden. Expression of the chemokine receptor CXCR4 on human CD20 + CD3 - CD27 + CD43 + B1 cells associated with reduced plaque burden in coronary arteries. No correlation was found between plaque volume and CXCR4 expression on naive or memory B cell subsets. Prior evidence demonstrates that the helix-loop-helix transcription factor Id3 regulates B cell homing to the aorta and B cell-mediated atheroprotection. Loss of Id3 in the Apoe -/- mouse model of atherosclerosis led to systemic increase in surface expression of CXCR4 on B1 cells. Loss of Id3 additionally led to attenuated lesion formation, as measured by immunohistochemical lesion analysis of the aorta. These data suggest a potential atheroprotective function of CXCR4 on B1 cells.
Optical Phased Array Electrical Beam Steering and Simulation

Optical phased array(OPA) is a new technology of beam steering and beam scanning.It has many advantages compared with traditional mechanical scanning.The principle of OPA electrical beam scanning is introduced.The influences of main parameters of OPA and the impact of Gauss beam to the steered beam quality are analyzed.At last three multi-beam scanning methods are demonstrated.The results show that in order to improve the steered beam quality,the unit period should be decreased,but the grating lobe can't be totally cleared.And the size of OPA and fill factor should be enlarged.The three multi-beam scanning methods which have their own specialty are all work.
Maternal breed of sire effects on postweaning performance of first-cross heifers and production characteristics of 2-year-old heifers.

Postweaning growth rates from weaning to 18 mo, fall condition score, pregnancy rates, and production to 2 yr of age were evaluated in a study of Angus (A)-, Pinzgauer (P)-, Red Poll (R)-, Simmental (S)-, and Tarentaise (T)-sired females from Hereford dams. First-cross heifers from the different sire breeds did not differ (P greater than .10) in initial weight. During a 140-d feed test, S gained 98.6 kg, exceeding (P less than .05) gains of P, 92.3; A, 91.4; and R, 87.3 kg but not T, 94.1 kg. Red Poll-sired heifers weighed less at the end of the 140-d test (P less than .05) than the other crosses, which did not significantly differ from each other. No breed of sire differences were found in gain from 140 d to fall weight. Simmental-sired heifers weighed more (P less than .05) than A- and R-sired heifers at 18 mo. Breed of sire and year interacted to affect pregnancy rate of the yearling heifers when mated to Shorthorn sires for 45 d. Percentage of dystocia varied from a low of 26.3 and 28.9% for T- and A-sired heifers, respectively, to 54.4 and 60.8% for P- and S-sired heifers, respectively (P less than .05). Age of dam of heifers affected (P less than .05) weight at the different period end points but not gains after weaning. Age of dam also affected incidence of dystocia. Two-year-old heifers from young dams had more dystocia than heifers from older dams. Shorthorn-sired calves from 2-yr-old heifers with different sire breeds differed in birth weight (P less than .05) but not survival from birth to weaning, ADG from birth to weaning, weaning age, or weaning condition score. Average 200-d weight of calves from P-, S- and T-sired heifers exceeded those from A- and R-sired heifers by 10.7 kg, or 5.7%.
Identification of Human Cathelicidin Peptide LL-37 as a Ligand for Macrophage Integrin α M β 2 (Mac-1, CD11b/CD18) that Promotes Phagocytosis by Opsonizing Bacteria

LL-37, a cationic antimicrobial peptide, has numerous immune-modulating effects. However, the identity of a receptor(s) mediating the responses in immune cells remains uncertain. We have recently demonstrated that LL-37 interacts with the αMI-domain of integrin αMβ2 (Mac-1), a major receptor on the surface of myeloid cells, and induces a migratory response in Mac-1-expressing monocyte/macrophages as well as activation of Mac-1 on neutrophils. Here, we show that LL-37 and its C-terminal derivative supported strong adhesion of various Mac-1-expressing cells, including HEK293 cells stably transfected with Mac-1, human U937 monocytic cells and murine IC-21 macrophages. The cell adhesion to LL-37 was partially inhibited by specific Mac-1 antagonists, including mAb against the αM integrin subunit and neutrophil inhibitory factor, and completely blocked when anti-Mac-1 antibodies were combined with heparin, suggesting that cell surface heparan sulfate proteoglycans act cooperatively with integrin Mac-1. Coating both Gram-negative and Gram-positive bacteria with LL-37 significantly potentiated their phagocytosis by macrophages, and this process was blocked by a combination of anti-Mac-1 mAb and heparin. Furthermore, phagocytosis by wild-type murine peritoneal macrophages of LL-37-coated latex beads, a model of foreign surfaces, was several fold higher than that of untreated beads. By contrast, LL-37 failed to augment phagocytosis of beads by Mac-1-deficient macrophages. These results identify LL-37 as a novel ligand for integrin Mac-1 and demonstrate that the interaction between Mac-1 on macrophages and bacteria-bound LL-37 promotes phagocytosis.
Redesigning healthcare to fit with people

Design expertise can improve delivery of care Healthcare expenditures vary fourfold across the globe, from less than 5% to nearly 20% of a nation’s gross domestic product.1 Higher levels of spending, however, have not necessarily produced better results, suggesting that some healthcare systems are more efficient than others.2 These observations have led to various efforts to improve the efficiency of care systems. In Europe and the US, for example, emphasis is increasingly shifting away from the “volume” of care (number of services) to the “value” of care (quality, outcomes, and costs).3 4 Government and other payers are driving health systems to invest in electronic health records, data analytics, performance improvement, and clinical decision support tools. Unfortunately, these investments are often launched as a series of individual fixes targeting different types of apparent underuse, overuse, or misuse of healthcare, disconnected from each other and from workflows in clinical settings. And thus well intentioned reforms are …
Smoking Increases the Rate of Reoperation for Infection within 90 Days After Primary Total Joint Arthroplasty.

Background: The relationship between smoking and complications after total joint arthroplasty is unclear. Prior studies have been limited by relatively small sample sizes or investigation of select cohorts. The purpose of this study was to investigate the association between smoking and readmission and/or reoperation within 90 days of total joint arthroplasty in a large, non-select cohort of patients. Methods: Using our institutional database, we retrospectively identified patients who underwent primary total joint arthroplasty between 2000 and 2014. Patients were stratified into 1 of 3 groups: current smokers, former smokers, and nonsmokers. The association between smoking status and subsequent readmission and/or reoperation within 90 days was investigated using multivariate regression analysis. Results: We retrospectively identified 15,264 patients (6,749 male and 8,515 female) who underwent 17,394 total joint arthroplasties during the study period. Of these patients, 1,371 (9.0%) were current smokers, 5,195 (34.0%) were former smokers, and 8,698 (57.0%) were nonsmokers. Former smokers reported a median of 22.2 years (range, 0.2 to 60 years) of abstinence prior to the surgical procedure. Current smokers were significantly younger (p < 0.001) at a mean age (and standard deviation) of 57.7 ± 10.3 years than nonsmokers at 63.2 ± 11.8 years. Current smokers were significantly more likely than nonsmokers to undergo reoperation for infection (odds ratio [OR], 1.82 [95% confidence interval (CI), 1.03 to 3.23]; p = 0.04), and former smokers were at no increased risk (OR, 1.11 [95% CI, 0.73 to 1.69]; p = 0.61). Packs per decade were independently associated with an increased risk of 90-day nonoperative readmission regardless of smoking status (OR, 1.12 [95% CI, 1.03 to 1.20]). Lastly, neither smoking status nor packs per decade were associated with aseptic or total reoperations. Conclusions: This study, after controlling for confounding factors, demonstrated not only that current smokers have a significantly increased risk of reoperation for infection within 90 days of a surgical procedure compared with nonsmokers, but also that the amount that one has smoked, regardless of current smoking status, significantly contributed to increased risk of nonoperative readmission. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
The lost art of lecturing: cultivating student listening and notetaking

Studies that systematically control the relevant features of lectures find significant learning benefits for students. However, the large-scale correlative studies of instructional format and stude...
Phase-Transfer Ligand Exchange of Lead Chalcogenide Quantum Dots for Direct Deposition of Thick, Highly Conductive Films

The use of semiconductor nanocrystal quantum dots (QDs) in optoelectronic devices typically requires postsynthetic chemical surface treatments to enhance electronic coupling between QDs and allow for efficient charge transport in QD films. Despite their importance in solar cells and infrared (IR) light-emitting diodes and photodetectors, advances in these chemical treatments for lead chalcogenide (PbE; E = S, Se, Te) QDs have lagged behind those of, for instance, II–VI semiconductor QDs. Here, we introduce a method for fast and effective ligand exchange for PbE QDs in solution, resulting in QDs completely passivated by a wide range of small anionic ligands. Due to electrostatic stabilization, these QDs are readily dispersible in polar solvents, in which they form highly concentrated solutions that remain stable for months. QDs of all three Pb chalcogenides retain their photoluminescence, allowing for a detailed study of the effect of the surface ionic double layer on electronic passivation of QD surfaces,...
Quartic polynomials having Galois closure of genus zero and their value sets

Abstract Let v be the number of distinct values of the polynomial f ( x ) = x 4 + a x 2 + b x , where a and b are elements of the finite field k of size q , where q is odd. When b is 0, an exact formula for v can be given. When b is not 0, as a consequence of the Tchebotarev Density Theorem, v = ( 5 / 8 ) q + O ( q ) . When the Galois closure of k ( x ) / k ( f ( x ) ) is a rational function field, v can be determined exactly. In this work we determine those f ( x ) 's for which this occurs and give the formula for v .
Parallel Chemistry Approach to Identify Novel Nuclear Receptor Ligands Based on the GW0742 Scaffold

We describe the parallel synthesis of novel analogs of GW0742, a peroxisome proliferator-activated receptor δ (PPARδ) agonist. For that purpose, modified reaction conditions were applied, such as a solid-phase palladium-catalyzed Suzuki coupling. In addition, tetrazole-based compounds were generated as a bioisostere for carboxylic acid-containing ligand GW0742. The new compounds were investigated for their ability to activate PPARδ mediated transcription and their cross-reactivity with the vitamin D receptor (VDR), another member of the nuclear receptor superfamily. We identified many potent PPARδ agonists that were less toxic than GW0742, where ∼65 of the compounds synthesized exhibited partial PPARδ activity (23–98%) with EC50 values ranging from 0.007–18.2 μM. Some ligands, such as compound 32, were more potent inhibitors of VDR-mediated transcription with significantly reduced PPARδ activity than GW0742, however, none of the ligands were completely selective for VDR inhibition over PPARδ activation of...
Mycolyltransferase from Mycobacterium tuberculosis in covalent complex with tetrahydrolipstatin provides insights into antigen 85 catalysis.

Mycobacterium tuberculosis antigen 85 (Ag85) enzymes catalyze the transfer of mycolic acid (MA) from trehalose monomycolate to produce the mycolyl arabinogalactan (mAG) or trehalose dimycolate (TDM). These lipids define the protective mycomembrane of mycobacteria. The current model of substrate binding within the active sites of Ag85s for the production of TDM is not sterically and geometrically feasible; additionally, this model does not account for the production of mAG. Furthermore, this model does not address how Ag85s limit the hydrolysis of the acyl-enzyme intermediate while catalyzing acyl transfer. To inform an updated model, we obtained an Ag85 acyl-enzyme intermediate structure that resembles the mycolated form. Here, we present a 1.45-A X-ray crystal structure of M. tuberculosis Ag85C covalently modified by tetrahydrolipstatin (THL), an esterase inhibitor that suppresses M. tuberculosis growth and mimics structural attributes of MAs. The mode of covalent inhibition differs from that observed in the reversible inhibition of the human fatty-acid synthase by THL. Similarities between the Ag85-THL structure and previously determined Ag85C structures suggest that the enzyme undergoes structural changes upon acylation, and positioning of the peptidyl arm of THL limits hydrolysis of the acyl-enzyme adduct. Molecular dynamics simulations of the modeled mycolated-enzyme form corroborate the structural analysis. From these findings, we propose an alternative arrangement of substrates that rectifies issues with the previous model and suggest a direct role for the β-hydroxy of MA in the second half-reaction of Ag85 catalysis. This information affords the visualization of a complete mycolyltransferase catalytic cycle.
Evaluation of a Ag/Ag2S reference electrode with long-term stability for electrochemistry in ionic liquids

Abstract We report on a reference electrode designed for use in ionic liquids, based on a silver wire coated with silver sulfide. The reference electrode potential is determined by the concentrations of Ag + and S 2− , which are established by the solubility of the Ag 2 S coating on the Ag wire. While potential shifts of >100 mV during an experiment have been reported when using silver or platinum wire quasi-reference electrodes, the reference electrode reported here provides a stable potential over several months of experimental use. Additionally, our reference electrode can be prepared and used in a normal air atmosphere, and does not need to be assembled and used in a glovebox, or protected from light. The reference electrode has been characterized by voltammetry measurements of ferrocene and cobaltocenium hexafluorophosphate, and was found to slowly drift to more positive potentials at a rate of
Rapid on-site evaluation using telecytology: A major cancer center experience.

Background Rapid on-site evaluation (ROSE) with cytology preparations plays a critical role in minimally invasive procedures. The time spent by a pathologist performing ROSE is unpredictable and could be used for more cost-effective activities. The solution encountered by several institutions to address this issue is the use of telecytology (TC). This study analyzes the experience of using telecytology for ROSE in a major cancer center over a period of over 2 years. Methods A retrospective analysis of all remote TC evaluations for adequacy on fine needle aspiration (FNA) and touch preparations (TP) of core biopsies (CB) performed at a major cancer center was performed. The preliminary adequacy assessment was then compared to the adequacy assessment at final diagnosis. Results A total of 12 949 adequacy assessments were analyzed. The most common sites biopsied in our institution were lymph node, lung, and liver. There were 7725 adequacy assessments for CB (59.7%), while adequacy assessment for FNA specimens represented 40.3% (n = 5224) of the total number of specimens evaluated by ROSE. Perfect concordance between initial adequacy assessment and the adequacy assessment at final cytologic diagnosis was 93% (12 049/12 949). The final diagnosis adequacy upgrade rate was 6.7% (n = 863), and the adequacy downgrade (a specimen considered adequate on-site that was determined to be nondiagnostic on final examination) was 0.3% (n = 37). Conclusions TC can be easily implemented with the current technologies available. It is cost-effective and allows for better patient care with a more efficient use of the pathologist's time and laboratory resources.
Incremental risk of long-term mortality with increased burden of comorbidity in hospitalized patients with pneumonia.

Abstract Background Patients hospitalized for pneumonia often have concurrent comorbid conditions (CCs). The influence of CCs on the risk of subsequent death is not fully understood. Methods We examined adults hospitalized for pneumonia between 1996 through 2015 at Mayo Clinic for the presence of 20 priori selected CCs. We estimated cumulative all-cause mortality by number of CCs using multivariable Cox regression model. Results Study comprised of 9580 adults (age 70 ± 17.0 years, men 53%, whites 88%) with median number of CCs 3 (interquartile 1–4), and overall deaths 6032 (62.9%) during 50,934 person-years of follow up (118.5 deaths/1000 person-years). After adjustment, any single comorbid condition was associated with 9% greater risk of death (95% confidence interval 1.08–1.11, P Conclusions Long-term mortality after hospitalization for pneumonia increases as the burden of comorbidities increases. Therefore, a simple comorbidity count help improve prognostic accuracy in identifying patients at increased risk of death following an episode of pneumonia.
Jonathan Cranfield, Twentieth-Century Victorian: Arthur Conan Doyle and the Strand Magazine, 1891–1930 (Edinburgh University Press, 2016)

Jonathan Cranfield. Twentieth-Century Victorian: Arthur Conan Doyle and the Strand Magazine, 1891–1930. Edinburgh Critical Studies in Victorian Culture. Edinburgh: Edinburgh University Press, 2016. £24.99
Five Financial Pearls for Medical Students, Residents, and Young Surgeons.

Background Finances impact every aspect of our daily lives. Despite this, they are rarely discussed in medical school or surgical training. Consequently, more than half the medical students we interview report no formal teaching about personal finance. The purpose of this article was to present 5 topics every graduating medical student, resident, and young surgeon should understand to start the path to financial independence. Methods We synthesized recommendations and data from several books on financial literacy, blogs on the topic, and the personal experiences of the 4 authors. Results The following 5 topics were identified as critical for young surgeons: learn about and manage your own finances, consider the financial implications of your career choices, make a plan to pay off your student loans, make a budget and stick to it, and think carefully before buying property. Central to these 5 lessons is the idea that starting to invest and save early is essential to taking advantage of interest and capital gains. We also demonstrate pay and cost differences in 5 regions of the country and outline the 2 main pathways one can take to repaying their student loans. Conclusions Financial literacy is an important aspect of being an effective surgeon. With minimal effort, you can take these 5 steps now toward financial freedom. Doing so will improve your sense of control over your financial life and decrease anxiety about the unknown.
Field testing a low-cost passive aerosol sampler for long-term measurement of ambient PM2.5 concentrations and particle composition

Abstract While low-cost sensors can be valuable in assessing patterns of exposure to PM2.5 in cities, few sensors are optimal for monitoring long-term averages, the metric most relevant to long-term mortality risk, and none can readily determine particle composition. This study was designed to field-test a low-cost passive sampler (University of North Carolina Passive Aerosol Sampler, UNC-PAS) to measure long-term mass and elemental concentrations of PM2.5 in urban areas. We collected sequential 4-week and 12-week integrated samples over 1 year at eight sites in Boston, New York City and the San Francisco Bay Area with co-located federal reference and/or equivalent PM2.5 samplers. Field blanks and duplicates were included to assess sampling artifacts and precision, respectively. We analyzed filters for PM2.5 concentrations and elemental composition by site and by city using computer-controlled scanning electron microscopy coupled with energy dispersive spectroscopy, combined with theoretical sampling rates based on particle diameter. To improve UNC-PAS performance for submicron, carbonaceous particles typical of urban environments, we developed and evaluated refinements to standard particle analysis methods and deposition calculations. The analysis improvements yielded better performance for samples heavily impacted by wildfires, while the calculation improvements yielded better agreement with continuous and filter data across all sites. We observed good precision, with a single sample error coefficient of variation of 14.2%. Compared with co-located filter and continuous methods, the passive samplers were, on average, accurate to within 13.6% and −1.0%, respectively. Microscopic elemental and morphological analysis of individual particles showed contributions from vehicle combustion, salts, aged salt-carbon mixtures, biogenic spores, fly ash, and wildfire smoke. We conclude that the UNC-PAS can be a useful, complementary approach for long-term community monitoring, with the potential to improve spatial coverage and provide valuable information on composition and sources.
Impact of Multi-Path Interference on Single Mode Transmission over Multi-Mode Fibers

Multi-Path Interference effect is analyzed in reduced core-diameter graded-index multimode fibers designed for both single-and multi-mode transmission. Reduction of MPI is shown to be practical through fiber core parameter optimization and connector misalignment mitigation.
Spin and Ferroic Glasses

Spin glasses are a broad class of magnetic materials that exhibit varying degrees of disorder and magnetic frustration, resulting in characteristic glassy relaxation behavior including frequency-dependent susceptibility, aging, and memory. Ferroic glasses include spin glasses and also relaxor ferroelectrics and strain glasses, which exhibit glassy dynamics in polarization and strain respectively, in similar ways to spin glasses. This chapter introduces ferroic and spin glasses, their phenomenological classification, and some parallels with structural (amorphous) glasses. A brief theoretical treatment is given, including modeling of the relaxation phenomena in ferroic glasses. Strain glasses and relaxors are discussed, followed by a detailed taxonomy of spin glasses and comparison with collectively behaving particle systems and structurally amorphous magnetic materials. Finally, some characteristic experimental methods are discussed, and an outlook for the future involvement of glass scientists in the study of spin glasses is offered.
Safety of Procedures During Pregnancy

There is limited information available on the safety and efficacy of gastrointestinal endoscopy in pregnant patients, with a majority of practice recommendations based on clinical reviews and case studies. During pregnancy it is critical to consider the potential harm to the fetus secondary to teratogenesis, hypoxia, trauma, or premature labor, and therefore all gastrointestinal endoscopic procedures performed during pregnancy should be undertaken by expert endoscopists. Informed consent should include not only risks to the mother but also risks to the fetus. To maximize efficacy and safety while minimizing maternal and fetal risks, a few important steps must be taken.
How Does a New General Surgery Residency Program's Junior Residents Impact Hospital Efficiency and Productivity?

Objective The general surgery workforce deficit is projected to grow to 15% to 21% by 2050. An estimated 6.6% increase to existing general surgery residency (GSR) programs is needed to meet this shortfall. The purpose of this study was to examine the impact of a new GSR program on efficiency and productivity at a regional healthcare center. Study design An institutional database was retrospectively queried for all GSR related procedures between July 2015 and June 2018. Procedures done prior to GSR initiation (pre-GSR) were compared to those done after (post-GSR). Univariate and multivariate analyses were performed. Results We reviewed 10,617 procedures (6365 pre-GSR vs. 4252 post-GSR). Patients had lower preoperative Hierarchical Condition Category scores in the post-GSR group (0.71 vs. 0.58, p Conclusion The initiation of a new GSR program did not negatively impact operative times, length of stay, 30-day readmissions and reoperations, hospital costs, case volume, or patient satisfaction.