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This research uses perfluorocarbons (PFCs) as effective alternatives to traditional toxic solvents in reversible para -hydrogen-induced polarization (PHIP) for NMR signal enhancement. Hydrogen solubility in PFCs is shown here to be an order of magnitude higher than in typical organic solvents by determination of Henry's constants. We demonstrate how this high H 2 solubility enables the PFCs to deliver substantial polarization transfer from para -hydrogen, achieving up to 2400-fold signal gains for 1 H NMR detection and 67,000-fold (22% polarization) for 15 N NMR detection at 9.4 T in substrates such as pyridine and nicotine. Notably, methylperfluorobutylether outperforms catalytic efficiency in methanol- d 4 and dichloromethane- d 2 for pyridine at low catalyst loadings. This makes PFCs particularly advantageous for applications demanding high NMR sensitivity. With high polarization efficiency and reduced toxicity, PFCs hold strong potential for expanding hyperpolarized NMR applications across the biomedical and analytical fields.

The neutral catalysts [IrCl(H) 2 (NHC)(substrate) 2 ] or [IrCl(H) 2 (NHC)(substrate)(sulfoxide)] are used to transfer polarization from para hydrogen ( p H 2 ) to 3,5-dichloropyridine and 3,5-dibromopyridine substrates. This is achieved in a rapid, reversible, and low-cost process that relies on ligand exchange within the active catalyst. Notably, the sulfoxide-containing catalyst systems produced NMR signal enhancements between 1 and 2 orders of magnitude larger than its unmodified counterpart. Consequently, this signal amplification by reversible exchange hyperpolarization method can boost the 1 H, 13 C, and 15 N nuclear magnetic resonance (NMR) signal intensities by factors up to 4350, 1550, and 46,600, respectively (14.0, 1.3, and 15.4% polarization). In this paper, NMR and X-ray crystallography are used to map the evolution of catalytically important species and provide mechanistic rational for catalytic efficiency. Furthermore, applications in spontaneous radiofrequency amplification by stimulated emission and NMR reaction monitoring are also shown., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

We report a case of human fascioliasis in the USA that encountered many diagnostic uncertainties. Numerous tests available for detection of fascioliasis were utilised but the diagnosis remained elusive. Confounders included three negative stool ova and parasite examinations, positive hepatitis A virus IgM antibody, cross-reactive false-positive Echinococcus IgG antibody, absence of characteristic image findings and unrevealing liver biopsy. Praziquantel was started as empiric treatment for helminth infections, but was ineffective. Due to the rarity of the disease in the USA, serologic testing and triclabendazole were only available from the Centers for Disease Control and Prevention, which led to a delay in diagnosis and treatment., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Transvaginal sonography (TVS) is a valuable primary imaging tool for the initial evaluation and management of endometriosis, a complex multifocal disease process with a varied spectrum of clinical and morphologic features that can substantially affect quality of life. The high accuracy of TVS for the detailed mapping of disease extent, an essential process for guiding treatment strategies, is well documented. The dynamic nature of US provides added value, revealing information that is not easily addressed with other imaging modalities. As recognized by the International Deep Endometriosis Analysis Consensus Group, a dedicated standardized protocol that is used by experienced and knowledgeable operators is necessary for a complete evaluation. The four components of a dedicated TVS protocol for evaluation of pelvic endometriosis are (a) evaluation of the uterus and adnexa, (b) dedicated search for deep infiltrating endometriosis, (c) assessment of the sliding sign, and (d) detection of sonographic soft markers. These components are described, and the multiple locations and US findings of endometriosis within the pelvis are reviewed, with emphasis on the unique features of US as an extension of the physical examination. In addition to enabling evaluation of the static findings of adenomyosis, endometrioma, hydrosalpinx, hematosalpinx, and hypoechoic nodules of deep infiltrating endometriosis, dynamic TVS enables assessment of pouch of Douglas obliteration, organ mobility, and site-specific tenderness, as well as tenderness-guided imaging. The benefits of implementing a dedicated TVS protocol in terms of improved patient care are also discussed. Online supplemental material is available for this article. © RSNA, 2019.

Objectives: To (1) evaluate the design and use of a global rating scale assessment instrument in veterinary medical education and; (2) examine the effectiveness of 2 surgical techniques courses for improving the surgical skills of veterinary students., Study Design: Instrument development; observational; survey-based., Sample Population: Students (n = 16) registered for 2 elective surgical techniques courses were enrolled on a volunteer basis., Methods: A 5-point global rating scale instrument was designed for the evaluation of 12 basic surgical skills by faculty evaluators and used to obtain student start and end scores during the courses. Upon conclusion of the courses, students completed a survey from which their opinions on their improvement as well as their desire for feedback were obtained., Results: All authors agreed the instrument was easy to use. As groups, 3rd year students, 4th year students, and all students combined had significantly higher total skill scores at the end of the courses compared to the start of the courses. Individually, 10 students (63%) had significant improvement in surgical skills as a result of their participation in the courses: 4 (100%) 3rd year and 6 (50%) 4th year students. Student survey responses revealed a strong desire for feedback as well as support of formal assessment methods. Only weak agreement was found between student opinions on their improvement and the authors' assessment scores., Conclusions: Assessment instruments are useful for (1) student evaluation and (2) for providing students with feedback on their surgical skills., (© Copyright 2013 by The American College of Veterinary Surgeons.)

Objectives: Video-assisted thoracoscopic surgery with talc pleurodesis is a therapeutic option for patients with hepatic hydrothorax that is refractory to medical therapy. We report the outcomes of 15 patients who underwent this procedure for significantly symptomatic disease., Methods: Data on 15 consecutive patients presenting to our institution between November, 1996, and June, 2000, with refractory hepatic hydrothorax was retrospectively collected. Baseline demographical and clinical characteristics and outcomes after the procedure were analyzed., Results: The mean age of our cohort was 51.5 yr, and eight (53%) of the 15 patients were male. The etiologies of liver disease were hepatitis C virus and/or alcohol (n = 12) and cryptogenic cirrhosis (n = 3). Nine patients were Child-Pugh class C and six class B. Success defined as control of symptomatic hydrothorax in the first 30 days after the procedure was achieved in 11 of 15 patients (73%). Eight of these patients remained asymptomatic at a median follow-up of 5.5 months after the procedure, but three patients experienced symptomatic fluid reaccumulation 45, 61, and 62 days after the initial procedure. After a second VATS procedure, control was achieved in two of these three patients. Complications included pain around the chest tube site, low grade fever with leukocytosis, pleurocutaneous fistula and empyema, all of which responded to medical therapy. Four patients did not respond to the procedure. There were no procedure-related deaths. Overall mortality and baseline clinical characteristics were similar between responders and nonresponders to VATS with pleurodesis., Conclusions: Symptomatic hepatic hydrothorax can be controlled with a single VATS with pleurodesis in as many as 53% of patients and with two procedures in 73% with no procedure-related mortality. The procedure may be considered as a palliative alternative in patients needing frequent thoracocentesis. It also provides an alternative to transjugular intrahepatic portosystemic shunts and is a bridge toward liver transplantation.

Technical limitations imposed by resolution and B1 homogeneity have thus far limited quantitative in vivo T2 mapping of cartilage to the patella. The purpose of this study is to develop T2 mapping of the femoral/tibial joint and assess regional variability of cartilage T2 in the knee. Quantitative in vivo T2 mapping of the knee was performed on 15 asymptomatic adults (age, 22-44) using a 3T MR scanner. There is a consistent pattern of spatial variation in cartilage T2 with longer values near the articular surface. The greatest variation occurs in the patella, where T2 increases from 45.3 +/- 2.5 msec at a normalized distance of 0.33-67 +/- 5.5 msec at a distance of 1.0. These results demonstrate feasibility of performing in vivo T2 mapping of femoral tibial cartilage. Except for the superficial 15% where T2 values are lower, the spatial variation in T2 of femoral and tibial cartilage is similar to patellar cartilage., (Copyright 2001 Wiley-Liss, Inc.)

We compared reflex responses to static handgrip at 30% maximal voluntary contraction (MVC) in 26 untrained men (mean age 35 +/- 3 yr) and 23 untrained women (mean age 39 +/- 4 yr). Women demonstrated attenuated increases in blood pressure and muscle sympathetic nerve activity (MSNA; by microneurography) compared with men. This difference was also observed during a period of posthandgrip circulatory arrest. 31P-nuclear magnetic resonance (NMR) spectroscopy studies demonstrated attenuations in the production of diprotonated phosphate and the development of cellular acidosis in women compared with men. Subjects also performed ischemic handgrip to fatigue. During this paradigm, MSNA responses were similar in the two groups, suggesting that freely perfused conditions are necessary for the full expression of the gender effect. Finally, we examined MSNA responses to adductor pollicus exercise in 7 men (26 +/- 1 yr) and 6 women (25 +/- 2 yr). MVC values and times to fatigue were similar in the two groups (MVC: men, 4.3 +/- 0.4 kg; women, 4.0 +/- 0.3 kg; not significant. Time to fatigue: men, 209 +/- 16 s; women, 287 +/- 50 s; not significant). At periods of end exercise and postexercise circulatory arrest, MSNA responses were attenuated in the women compared with the men. We conclude that, during nonischemic static exercise, sympathetic neural outflow is less in women compared with men. This response is due to an attenuated metaboreflex in women. Finally, on the basis of the adductor pollicus experiments, this effect appears independent of muscle mass, workload, and the level of training.

Judging from advertisements for professional books, continuing education workshops, and speakers, social workers appear to believe that codependency is a problem about which they should be knowledgeable. This article traces the evolution of the codependency construct and its burgeoning popularity in the 1980s. It critically examines codependency from the perspective of researchers who have found little empirical support for the constellation of characteristics used to define the term and from the perspective of feminist analysis. In addition, the article analyzes the assumptions about health and relationships that are embedded in the concept of the codependency and contends, from the perspective of self-in-relation theory, that the concept does not provide a useful framework for social work conceptualization and intervention with women.

1. Seasonal variations in unit perching costs, flying costs and energy budgets for Lichmera indistincta were investigated. 2. Unit perching and flying costs were greatest in winter and least in summer. Variations in perching costs occurred principally because of changes in conductance. Flying cost variations may have been due to changes in wing disc loading and/or the integrity of wing feathers. 3. Rates of net energy intake were greatest in winter and least in summer. Variations in these rates were such that they offset changes in the rates of total energy expenditure to provide diurnal energy balance. 4. Regardless of the season, net daytime energy storage proceeded at a uniform rate and resulted in the storage of sufficient energy to offset overnight expenditure.