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1.
Sci Rep ; 14(1): 3592, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38351145

RESUMEN

Quantum algorithms provide an exponential speedup for solving certain classes of linear systems, including those that model geologic fracture flow. However, this revolutionary gain in efficiency does not come without difficulty. Quantum algorithms require that problems satisfy not only algorithm-specific constraints, but also application-specific ones. Otherwise, the quantum advantage carefully attained through algorithmic ingenuity can be entirely negated. Previous work addressing quantum algorithms for geologic fracture flow has illustrated core algorithmic approaches while incrementally removing assumptions. This work addresses two further requirements for solving geologic fracture flow systems with quantum algorithms: efficient system state preparation and efficient information extraction. Our approach to addressing each is consistent with an overall exponential speed-up.

2.
Clin Kidney J ; 16(1): 176-183, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36726438

RESUMEN

Background: Hyperkalemia (HK) is a frequent condition in patients with chronic kidney disease (CKD) that is associated with high morbidity and mortality. Patiromer has recently been introduced as a potassium binder. Data on patiromer use in patients with CKD in the real-world setting in Europe are lacking. We describe time to discontinuation and changes in serum potassium levels among German CKD stage 3-5 patients starting patiromer. Methods: Duration of patiromer use was estimated by Kaplan-Meier curve, starting at patiromer initiation and censoring for death, dialysis, transplant or loss to follow-up. Serum potassium levels and renin-angiotensin-aldosterone system inhibitor (RAASi) use are described at baseline and during follow-up, restricted to patients remaining on patiromer. Results: We identified 140 patiromer users within our analysis sample [81% CKD stage 4/5, 83% receiving RAASi, and median K+ 5.7 (5.4, 6.3) mmol/L]. Thirty percent of patiromer users had prior history of polystyrene sulfonate use. Overall, 95% of patiromer users stayed on treatment past 1 month, with 53% continuing for over a year. Mean serum potassium levels decreased after patiromer initiation and remained stable under treatment during follow-up (up to 180 days). Among these patients, 73%-82% used RAASis during the time periods before and after patiromer initiation, with no obvious trend indicating discontinuation. Conclusion: Real-world evidence of patiromer use in Germany shows that, in line with what has been observed in clinical trials, patients on patiromer have a reduction in serum potassium when used long-term. Moreover, most patients on patiromer do not discontinue treatment prior to 1 year after initiation.

3.
Sci Rep ; 13(1): 2906, 2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36805641

RESUMEN

Solving large systems of equations is a challenge for modeling natural phenomena, such as simulating subsurface flow. To avoid systems that are intractable on current computers, it is often necessary to neglect information at small scales, an approach known as coarse-graining. For many practical applications, such as flow in porous, homogenous materials, coarse-graining offers a sufficiently-accurate approximation of the solution. Unfortunately, fractured systems cannot be accurately coarse-grained, as critical network topology exists at the smallest scales, including topology that can push the network across a percolation threshold. Therefore, new techniques are necessary to accurately model important fracture systems. Quantum algorithms for solving linear systems offer a theoretically-exponential improvement over their classical counterparts, and in this work we introduce two quantum algorithms for fractured flow. The first algorithm, designed for future quantum computers which operate without error, has enormous potential, but we demonstrate that current hardware is too noisy for adequate performance. The second algorithm, designed to be noise resilient, already performs well for problems of small to medium size (order 10-1000 nodes), which we demonstrate experimentally and explain theoretically. We expect further improvements by leveraging quantum error mitigation and preconditioning.

4.
Sex Transm Infect ; 99(4): 283-284, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36707246

RESUMEN

We present an apparent second episode of mpox (monkeypox) genital ulcerative disease in a non-immunosuppressed MSM (man who has sex with men) patient who had completely recovered from a primary mpox infection 4 months previously. The patient had also received a complete two-dose course of smallpox vaccination between the two presentations. This case highlights the importance of continuing to include mpox in the differential diagnoses for individuals presenting with genital or mucosal ulceration, regardless of assumed immunity derived from prior infection or vaccination.


Asunto(s)
Mpox , Minorías Sexuales y de Género , Enfermedades Urogenitales , Masculino , Humanos , Homosexualidad Masculina , Reinfección , Diagnóstico Diferencial
5.
Sex Transm Infect ; 99(2): 138-139, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36585024

RESUMEN

We present a case of a transgender man symptomatic of vaginal Neisseria gonorrhoeae infection despite reporting no receptive vaginal sex in his recent history.


Asunto(s)
Gonorrea , Personas Transgénero , Transexualidad , Masculino , Femenino , Humanos , Gonorrea/diagnóstico , Neisseria gonorrhoeae , Vagina , Homosexualidad Masculina
6.
Clin Infect Dis ; 76(3): e1424-e1427, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36052417

RESUMEN

We describe 2 cases of infectious proctitis secondary to human monkeypox in patients presenting with rectal pain. These cases highlight the importance of multidisciplinary management of monkeypox and in expanding case definitions and enabling clinical recognition in patients presenting without skin rash.


Asunto(s)
Exantema , Infecciones Intraabdominales , Mpox , Proctitis , Humanos , Proctitis/diagnóstico , Proctitis/tratamiento farmacológico , Dolor
7.
Sci Rep ; 12(1): 22285, 2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36566269

RESUMEN

Modeling hydrological fracture networks is a hallmark challenge in computational earth sciences. Accurately predicting critical features of fracture systems, e.g. percolation, can require solving large linear systems far beyond current or future high performance capabilities. Quantum computers can theoretically bypass the memory and speed constraints faced by classical approaches, however several technical issues must first be addressed. Chief amongst these difficulties is that such systems are often ill-conditioned, i.e. small changes in the system can produce large changes in the solution, which can slow down the performance of linear solving algorithms. We test several existing quantum techniques to improve the condition number, but find they are insufficient. We then introduce the inverse Laplacian preconditioner, which improves the scaling of the condition number of the system from O(N) to [Formula: see text] and admits a quantum implementation. These results are a critical first step in developing a quantum solver for fracture systems, both advancing the state of hydrological modeling and providing a novel real-world application for quantum linear systems algorithms.

8.
Materials (Basel) ; 15(19)2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36234142

RESUMEN

A method is presented for generating free energies relating to nonlinear constitutive equations with memory from known free energies associated with hereditary linear theories. Some applications to viscoelastic solids and hereditary electrical conductors are presented. These new free energies are then used to obtain estimates for nonlinear integro-differential evolution problems describing the behavior of nonlinear plasmas with memory.

9.
PLoS One ; 16(1): e0244026, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33406162

RESUMEN

It was recently shown that quantum annealing can be used as an effective, fast subroutine in certain types of matrix factorization algorithms. The quantum annealing algorithm performed best for quick, approximate answers, but performance rapidly plateaued. In this paper, we utilize reverse annealing instead of forward annealing in the quantum annealing subroutine for nonnegative/binary matrix factorization problems. After an initial global search with forward annealing, reverse annealing performs a series of local searches that refine existing solutions. The combination of forward and reverse annealing significantly improves performance compared to forward annealing alone for all but the shortest run times.


Asunto(s)
Algoritmos , Modelos Teóricos , Teoría Cuántica
12.
Arch Phys Med Rehabil ; 91(11): 1673-83, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21044711

RESUMEN

Empirical studies and surveillance projects increasingly assess and address potentially adverse psychological health outcomes from the stress of military operations, but no standards yet exist for common concept definitions, variable categories, and measures. This article reports the consensus recommendations of the federal interagency Operational Stress Working Group for common data elements to be used in future operational stress research and surveillance with the goal of improving comparability across studies. Operational stress encompasses more than just combat; it occurs everywhere service members and their families live and work. Posttraumatic stress is not the only adverse mental or behavioral health outcome of importance. The Operational Stress Working Group contends that a primary goal of operational stress research and surveillance is to promote prevention of adverse mental and behavioral outcomes, especially by recognizing the preclinical and subclinical states of distress and dysfunction that portend a risk for failure of role performance or future mental disorders. Recommendations for data elements are divided into 3 tiers: core, supplemental, and emerging, including variable domains and specific measures for assessing operational stressor exposures, stress outcomes, moderating factors, and mediating processes. Attention is drawn to the emerging construct of stress injury as a generic term for subclinical operational stress, and to emerging data elements addressing biological, psychological, and spiritual mediators of risk. Methodologies are needed for identifying preclinical and subclinical states of distress or dysfunction that are markers of risk for failure of role performance and future clinical mental disorders, so that targeted prevention interventions can be developed and evaluated.


Asunto(s)
Consenso , Recolección de Datos/métodos , Gobierno Federal , Relaciones Interinstitucionales , Investigación Operativa , Guías de Práctica Clínica como Asunto/normas , Trastornos por Estrés Postraumático/rehabilitación , Humanos , Personal Militar , Estados Unidos
13.
J Law Med Ethics ; 38(2): 314-31, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20579254

RESUMEN

While society debates whether and how to use public funds to support work on human embryonic stem cells (hESCs), many scientific groups and businesses debate a different question - the extent to which patents that cover such stem cells should be permitted to limit or to tax their research. The Wisconsin Alumni Research Foundation (WARF), a non-profit foundation that manages intellectual property generated by researchers at the University of Wisconsin at Madison, owns three patents that have been at the heart of the latter controversy The story of WARF's patents and the controversy they have fostered highlights not only continuing tensions between proprietary and nonproprietary approaches to developing science and technology, but also an at least partly reassuring capacity of public and private sectors to deal with those tensions in a way that can render them substantially manageable, and frequently more manageable as a technology matures. More particularly, the cumulative story of WARF's patents features three leitmotifs that suggest how an attentive and engaged public sector might commonly succeed in working with public and private sector actors to achieve workable balances between proprietary rights and more general social interests: (1) right holders' decisions to pursue less than full rights assertion or enforcement; (2) the ability of government and other public sector actors to help bring about such decisions through co-option or pressure; and (3) the frequent availability or development of technological alternatives that limit research bottlenecks.


Asunto(s)
Investigaciones con Embriones/ética , Fundaciones/ética , Patentes como Asunto/ética , Sector Privado/ética , Sector Público/ética , Apoyo a la Investigación como Asunto/ética , Animales , Mercantilización , Disentimientos y Disputas , Investigaciones con Embriones/legislación & jurisprudencia , Células Madre Embrionarias , Europa (Continente) , Fundaciones/organización & administración , Regulación Gubernamental , Humanos , Principios Morales , National Institutes of Health (U.S.)/organización & administración , Organizaciones sin Fines de Lucro/ética , Organizaciones sin Fines de Lucro/organización & administración , Patentes como Asunto/legislación & jurisprudencia , Células Madre Pluripotentes , Primates , Sector Privado/organización & administración , Sector Público/organización & administración , Apoyo a la Investigación como Asunto/legislación & jurisprudencia , Apoyo a la Investigación como Asunto/organización & administración , Estados Unidos , Wisconsin
14.
Circulation ; 113(18): 2201-10, 2006 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-16651474

RESUMEN

BACKGROUND: Hypertension is a major cause of heart failure (HF) and is antecedent in 91% of cases. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) stipulated assessment of the relative effect of chlorthalidone, lisinopril, and amlodipine in preventing HF. METHODS AND RESULTS: ALLHAT was a double-blind, randomized, clinical trial in 33,357 high-risk hypertensive patients aged > or =55 years. Hospitalized/fatal HF outcomes were examined with proportional-hazards models. Relative risks (95% confidence intervals; P values) of amlodipine or lisinopril versus chlorthalidone were 1.35 (1.21 to 1.50; <0.001) and 1.11 (0.99 to 1.24; 0.09). The proportional hazards assumption of constant relative risk over time was not valid. A more appropriate model showed relative risks of amlodipine or lisinopril versus chlorthalidone during year 1 were 2.22 (1.69 to 2.91; <0.001) and 2.08 (1.58 to 2.74; <0.001), and after year 1, 1.22 (1.08 to 1.38; P=0.001) and 0.96 (0.85 to 1.10; 0.58). There was no significant interaction between prior medication use and treatment. Baseline blood pressures were equivalent (146/84 mm Hg) and at year 1 were 137/79, 139/79, and 140/80 mm Hg in those given chlorthalidone, amlodipine, and lisinopril. At 1 year, use of added open-label atenolol, diuretics, angiotensin-converting enzyme inhibitors, and calcium channel blockers in the treatment groups was similar. CONCLUSIONS: HF risk decreased with chlorthalidone versus amlodipine or lisinopril use during year 1. Subsequently, risk for those individuals taking chlorthalidone versus amlodipine remained decreased but less so, whereas it was equivalent to those given lisinopril. Prior medication use, follow-up blood pressures, and concomitant medications are unlikely to explain most of the HF differences. Diuretics are superior to calcium channel blockers and, at least in the short term, angiotensin-converting enzyme inhibitors in preventing HF in hypertensive individuals.


Asunto(s)
Antihipertensivos/uso terapéutico , Clortalidona/uso terapéutico , Diuréticos/uso terapéutico , Insuficiencia Cardíaca/prevención & control , Hipertensión/tratamiento farmacológico , Antagonistas Adrenérgicos beta/uso terapéutico , Anciano , Amlodipino/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Atenolol/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Método Doble Ciego , Doxazosina/uso terapéutico , Quimioterapia Combinada , Femenino , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/mortalidad , Hospitalización/estadística & datos numéricos , Humanos , Hipertensión/complicaciones , Incidencia , Lisinopril/uso terapéutico , Masculino , Persona de Mediana Edad , Infarto del Miocardio/prevención & control , Modelos de Riesgos Proporcionales , Riesgo , Resultado del Tratamiento
15.
Curr Control Trials Cardiovasc Med ; 3(1): 10, 2002 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-12459039

RESUMEN

BACKGROUND: The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized, double-blind, active-controlled trial designed to compare the rate of coronary heart disease events in high-risk hypertensive participants initially randomized to a diuretic (chlorthalidone) versus each of three alternative antihypertensive drugs: alpha-adrenergic blocker (doxazosin), ACE-inhibitor (lisinopril), and calcium-channel blocker (amlodipine). Combined cardiovascular disease risk was significantly increased in the doxazosin arm compared to the chlorthalidone arm (RR 1.25; 95% CI, 1.17-1.33; P <.001), with a doubling of heart failure (fatal, hospitalized, or non-hospitalized but treated) (RR 2.04; 95% CI, 1.79-2.32; P <.001). Questions about heart failure diagnostic criteria led to steps to validate these events further. METHODS AND RESULTS: Baseline characteristics (age, race, sex, blood pressure) did not differ significantly between treatment groups (P <.05) for participants with heart failure events. Post-event pharmacologic management was similar in both groups and generally conformed to accepted heart failure therapy. Central review of a small sample of cases showed high adherence to ALLHAT heart failure criteria. Of 105 participants with quantitative ejection fraction measurements provided, (67% by echocardiogram, 31% by catheterization), 29/46 (63%) from the chlorthalidone group and 41/59 (70%) from the doxazosin group were at or below 40%. Two-year heart failure case-fatalities (22% and 19% in the doxazosin and chlorthalidone groups, respectively) were as expected and did not differ significantly (RR 0.96; 95% CI, 0.67-1.38; P = 0.83). CONCLUSION: Results of the validation process supported findings of increased heart failure in the ALLHAT doxazosin treatment arm compared to the chlorthalidone treatment arm.

16.
Arch. pediatr. Urug ; 62(1/4): 3-10, 1991. tab
Artículo en Español | LILACS | ID: lil-189802

RESUMEN

El Síndrome de Dificultad Respiratoria (SDR) del recién nacido en parte es debido, a la ausencia o, marcada disminución del surfactante pulmonar. La enfermedad se caracteriza por la presencia de una pobre distensibilidad pulmonar debida a una deficiencia funcional o cuantitativa del surfactante que origina un progresivo colapso de los pulmones. La administración de surfactantes exógenos provenientes de mamíferos, humanos y artificiales están siendo investigados para su uso en prematuros y promete reducir la severidad, morbilidad y mortalidad atribuible al SDR. Este surfactante exógeno ("Exosurf") produce importantes cambios en la fisiología pulmonar que puede tener impacto sobre el sistema cardiovascular. Algunos de ellos pueden tener impacto sobre el sistema cardiovascular. Algunos de ellos, pueden afectar por ejemplo, la velocidad del flujo sanguíneo cerebral (VFSC) cuyas variaciones pueden estar relacionadas con la aparicion de hemorragias intraventriculares (HIV), una de las más importantes enfermedades del recién nacido prematuro. Los objetivos del presente estudio son: 1.- Documentar los cambios agudos en la circulación cerebral en neonatos que recibieron surfactante intratraqueal midiendo las VFSC en la arteria carótida interna antes y después de la primera o segunda dosis de "Exosurf". 2.- Estudiar la asociación de los cambios de las VFSC después de la administración de surfactante con las variaciones registradas en la presión arterial, gases en sangre y el desarrollo o extensión de HIV. Para ello la Velocidad del Flujo Sanguíneo Cerebral (VFSC), fue estudiada en las arterias carótidas a través de la fontanela anterior, utilizando la ecografía cerebral para localización de las arterias y el Doppler para realizar las medidas de la VFSC. La misma técnica se utilizó para diagnosticar la localización y extensión de las HIV. (RESUMEN TRUNCADO)


Asunto(s)
Humanos , Recién Nacido , Hemorragia Cerebral , Cerebro/irrigación sanguínea , Flujo Sanguíneo Regional , Surfactantes Pulmonares , Síndrome de Dificultad Respiratoria del Recién Nacido , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/etiología , Surfactantes Pulmonares/administración & dosificación , Surfactantes Pulmonares/efectos adversos , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico
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