Energetic Cost of Measurements Using Quantum, Coherent, and Thermal Light.

Quantum measurements are basic operations that play a critical role in the study and application of quantum information. We study how the use of quantum, coherent, and classical thermal states of light in a circuit quantum electrodynamics setup impacts the performance of quantum measurements, by comparing their respective measurement backaction and measurement signal to noise ratio per photon. In the strong dispersive limit, we find that thermal light is capable of performing quantum measurements with comparable efficiency to coherent light, both being outperformed by single-photon light. We then analyze the thermodynamic cost of each measurement scheme. We show that single-photon light shows an advantage in terms of energy cost per information gain, reaching the fundamental thermodynamic cost.

Closed-System Solution of the 1D Atom from Collision Model.

Obtaining the total wavefunction evolution of interacting quantum systems provides access to important properties, such as entanglement, shedding light on fundamental aspects, e.g., quantum energetics and thermodynamics, and guiding towards possible application in the fields of quantum computation and communication. We consider a two-level atom (qubit) coupled to the continuum of travelling modes of a field confined in a one-dimensional chiral waveguide. Originally, we treated the light-matter ensemble as a closed, isolated system. We solve its dynamics using a collision model where individual temporal modes of the field locally interact with the qubit in a sequential fashion. This approach allows us to obtain the total wavefunction of the qubit-field system, at any time, when the field starts in a coherent or a single-photon state. Our method is general and can be applied to other initial field states.

Naloxone decreases the inhibitory effect of alprazolam on the release of adrenocorticotropin/cortisol induced by physical exercise in man.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Alprazolam (ALP), a benzodiazepine activating GABAergic receptors, is involved in ACTH secretion. WHAT THIS STUDY ADDS: • This study demonstrates a partial opioid influence in the inhibitory effect of ALP on the release of ACTH/cortisol during physical exercise. AIMS: To establish the possible involvement of alprazolam (ALP) and/or opiates in the mechanism underlying the ACTH/cortisol response to physical exercise. METHODS: Tests were carried out under basal conditions (exercise control test), exercise plus ALP (50 µg at time -90 min), naloxone (10 mg at time 0) or ALP plus naloxone. Plasma ACTH and serum cortisol concentrations were evaluated in blood samples taken before, during and after the bicycle ergometer tests. RESULTS: ACTH and cortisol concentrations rose significantly after physical exercise. Maximum peak at time 15 min (P ≤ 0.01 vs. baseline) for ACTH and at time 30 min (P ≤ 0.01 vs. baseline) for cortisol. In the presence of naloxone, the ACTH and cortisol responses were significantly increased (maximum peak at time 20 min, P ≤ 0.02 vs. control test for ACTH, and at time 30 min (P ≤ 0.01 vs. baseline) for cortisol) whereas they were abolished by ALP. When ALP and naloxone were given together, the inhibitory effect of ALP was partial. CONCLUSIONS: These data demonstrate an inhibitory effect of ALP in the regulation of the ACTH/cortisol response to physical exercise in man and suggest that GABAergic receptor activating benzodiazepines and opioids interact in the neuroendocrine secretion of ACTH/cortisol.

Observation of the topological Anderson insulator in disordered atomic wires.

Topology and disorder have a rich combined influence on quantum transport. To probe their interplay, we synthesized one-dimensional chiral symmetric wires with controllable disorder via spectroscopic Hamiltonian engineering, based on the laser-driven coupling of discrete momentum states of ultracold atoms. Measuring the bulk evolution of a topological indicator after a sudden quench, we observed the topological Anderson insulator phase, in which added disorder drives the band structure of a wire from topologically trivial to nontrivial. In addition, we observed the robustness of topologically nontrivial wires to weak disorder and measured the transition to a trivial phase in the presence of strong disorder. Atomic interactions in this quantum simulation platform may enable realizations of strongly interacting topological fluids.

Effects of moderate ethanol drinking on the GH and cortisol responses to physical exercise.

OBJECTIVE: To evaluate the effects of moderate amounts of ethanol on the GH and cortisol responses to physical exercise. METHODS: Ten normal men underwent three bicycle ergometer tests. Test were carried out in basal conditions (control test) or after drinking 0.5 or 0.75 g/kg BW ethanol. Tests lasted 15 min in all subjects; the workload was increased at 3 min intervals from time 0 until exhaustion. Non-endocrine physiological parameters (NEPP), such as heart rate, blood pressure, ventilation, frequency of breathing, tidal volume, oxygen consumption, carbon oxide production and respiratory exchange ratio were measured from time 0 until exhaustion. Serum GH and cortisol levels were evaluated in blood samples taken at 5-10 min intervals over a 50 min period from time 0. RESULTS: Neither basal values, nor exercise-induced changes in NEPP were altered by ethanol drinking. Both GH and cortisol levels significantly rose during the exercise control test. The hormonal responses did not change after 0.5 g/kg BW ethanol, whereas they significantly decreased after 0.75 g/kg BW ethanol. CONCLUSIONS: Modification of the GH and cortisol responses to exercise represents an "endocrine window" of the effects that even moderate ethanol drinking produces in the CNS. The data show that 0.75 g/kg BW ethanol is the minimal amount producing significant inhibitory effects on the GH and cortisol responses to physical exercise. In view of the important roles played by GH and cortisol during physical activity, even moderate ethanol drinking must be avoided before sport.

Topological features of vector vortex beams perturbed with uniformly polarized light.

Optical singularities manifesting at the center of vector vortex beams are unstable, since their topological charge is higher than the lowest value permitted by Maxwell's equations. Inspired by conceptually similar phenomena occurring in the polarization pattern characterizing the skylight, we show how perturbations that break the symmetry of radially symmetric vector beams lead to the formation of a pair of fundamental and stable singularities, i.e. points of circular polarization. We prepare a superposition of a radial (or azimuthal) vector beam and a uniformly linearly polarized Gaussian beam; by varying the amplitudes of the two fields, we control the formation of pairs of these singular points and their spatial separation. We complete this study by applying the same analysis to vector vortex beams with higher topological charges, and by investigating the features that arise when increasing the intensity of the Gaussian term. Our results can find application in the context of singularimetry, where weak fields are measured by considering them as perturbations of unstable optical beams.

Detection of Zak phases and topological invariants in a chiral quantum walk of twisted photons.

Topological insulators are fascinating states of matter exhibiting protected edge states and robust quantized features in their bulk. Here we propose and validate experimentally a method to detect topological properties in the bulk of one-dimensional chiral systems. We first introduce the mean chiral displacement, an observable that rapidly approaches a value proportional to the Zak phase during the free evolution of the system. Then we measure the Zak phase in a photonic quantum walk of twisted photons, by observing the mean chiral displacement in its bulk. Next, we measure the Zak phase in an alternative, inequivalent timeframe and combine the two windings to characterize the full phase diagram of this Floquet system. Finally, we prove the robustness of the measure by introducing dynamical disorder in the system. This detection method is extremely general and readily applicable to all present one-dimensional platforms simulating static or Floquet chiral systems.

Statistical moments of quantum-walk dynamics reveal topological quantum transitions.

Many phenomena in solid-state physics can be understood in terms of their topological properties. Recently, controlled protocols of quantum walk (QW) are proving to be effective simulators of such phenomena. Here we report the realization of a photonic QW showing both the trivial and the non-trivial topologies associated with chiral symmetry in one-dimensional (1D) periodic systems. We find that the probability distribution moments of the walker position after many steps can be used as direct indicators of the topological quantum transition: while varying a control parameter that defines the system phase, these moments exhibit a slope discontinuity at the transition point. Numerical simulations strongly support the conjecture that these features are general of 1D topological systems. Extending this approach to higher dimensions, different topological classes, and other typologies of quantum phases may offer general instruments for investigating and experimentally detecting quantum transitions in such complex systems.

Arthroscopic ganglion cyst excision in the anterolateral aspect of the knee.

We present a case of ganglion cyst of the knee treated arthroscopically. Ganglion cysts typically arise from the anterior or the posterior cruciate ligament. In this case of an anomalous location, a 3.5-cm mass arose directly from the anterolateral articular capsule, lying over the lateral meniscus, displacing Hoffa's fat pad and joining the pretibial bursa. We removed it arthroscopically using only medial portals to avoid cystic wall damage and fluid leakage from the lateral portal. Arthroscopic evaluation was performed starting from the inferomedial portal to assess the cyst location, and shifting to the mid patellar portal. From that portal, we were able resect the cyst, opening the wall and shaving and aspirating the myxoid fluid.

Inhibitory effect of dexamethasone on arginine-vasopressin release induced by physical exercise in man.

To establish whether glucocorticoids inhibit the arginine-vasopressin (AVP) response to physical exercise, 10 healthy men underwent bicycle ergometer tests until exhaustion (exercise control test, exercise plus dexamethasone [2 or 4 mg in an intravenous bolus]). Physiological and biochemical variables were similar in all tests. Pretreatment with dexamethasone (2 or 4 mg) partially but significantly decreased the AVP response induced by physical exercise. Our results demonstrate a partial inhibition induced by glucocorticoids of AVP neurosecretion during cycle ergometer tests.

Disfunción tiroidea en pacientes con diabetes mellitus tipo 2: ¿Una asociación frecuente?

Introducción: la disfunción tiroidea (DT) se observa con frecuencia en pacientes con diabetes mellitus tipo 2 (DM2) siendo el hipotiroidismo es el más frecuente. Objetivos: determinar frecuencia de DT en pacientes con DM2, que consultan en la Primera Cátedra de Clínica Médica del Hospital de Clínicas (San Lorenzo, Paraguay), de enero a diciembre del 2013. Material y Métodos: diseño observacional, retrospectivo, analítico. Incluimos pacientes de ambos sexos, mayores de 18 años. Excluimos pacientes con fármacos que afecten función tiroidea, tiroidectomizados, enfermos renales crónicos. Resultados: incluimos 254 pacientes, encontramos DT en 9,45% (n 24), diagnóstico previo 8,26% (n 21) y nuevos casos 1,18 % (n 3). Presentaron hipotiroidismo 66,7 % (n 16), siendo hipotiroidismo clínico 41,6% (n 10) e hipotiroidismo subclínico 25% (n 6). Hallamos hipertiroidismo en 33,3 (n 8), siendo hipertiroidismo clínico 20,8% (n 5) e hipertiroidismo subclínico 12,5% (n 3). De los 254 pacientes, 179 fueron mujeres (22 con DT) y 97 varones (2 con DT), (OR 6,6 (1,5-28,9) p 0,003); 126 eran mayores de 50 años (17 con DT) y 128 eran < 50 años (7 con DT): (OR 2,6 (1,1-6,7) p 0,03). Conclusiones: la frecuencia de DT en pacientes con DM2 fue 9,45%, con predominio en mujeres y mayores de 50 años, siendo más frecuente el hipotiroidismo clínico.

Introduction: Thyroid dysfunction (TD) is frequently observed in Type 2 diabetes mellitus (DM2) patients being the hypothyroidism the most common. Objectives: To determine the frequency of TD in DM2 patients consulting at the Fist Chair of Medical Clinic of the Hospital de Clínicas (San Lorenzo, Paraguay) from January to December, 2013. Material and Methods: Analytical retrospective observational design that included men and women older than 18 years old. We excluded patients receiving drugs that affect thyroid function, those that were thyroidectomized and chronic renal patients. Results: We included 254 patients and found DT in 9.45% (n=24), previous diagnosis 8.26% (n=21) and new cases 1.18 % (n=3). We found hypothyroidism in 66.7 % (n=16), being clinical hypothyroidism 41.6% (n=10) of them and sub-clinical hypothyroidism 25% (n=6). Also, we determined hyperthyroidism in 33.3 (n=8), being clinical hyperthyroidism 20.8% (n=5) of them and sub-clinical hyperthyroidism 12.5% (n=3). Out of the 254 patients, 179 were women (22 with TD) and 97 men (2 with TD), (OR 6.6 (1.5-28.9) p = 0.003); 126 were older than 50 years old (17 with TD) and 128 were < 50 years old (7 with TD): (OR 2.6 (1.1-6.7) p= 0.03). Conclusions: The frequency of TD in DM2 patients was 9.45%, with predominance in women and in those older than 50 years being the most frequent dysfunction, clinical hypothyroidism.

Effect of naloxone on the inhibitory effect of melatonin on the release of arginine-vasopressin induced by physical exercise in man.

This study was performed in order to establish whether endogenous opioids play a role in the inhibitory effect of melatonin on arginine-vasopressin (AVP) response to physical exercise. Seven healthy men underwent four bicycle ergometer tests until exhaustion [exercise control test, exercise plus naloxone (2mg injected plus 5mg infused intravenously), exercise plus melatonin (6mg), exercise plus melatonin plus naloxone]. Plasma AVP concentrations, non endocrine physiological parameters (NEPP) and biochemical parameters were evaluated during all tests. NEPP and biochemical values had a similar pattern during all tests. Physical exercise significantly increased the AVP levels. The pre-treatment with melatonin inhibited the AVP response to physical exercise. In contrast, naloxone had no effect on AVP rise during exercise, when given alone, whereas it abolished the negative effect of melatonin on AVP response to physical exercise. Our data indicate that naloxone-sensitive endogenous opiates mediate the inhibitory modulation exerted by melatonin on the AVP response to physical exercise.

Effect of physical training on age-related reduction of GH secretion during exercise in normally cycling women.

OBJECTIVE: To evaluate whether prolonged physical activity (25 km/week running for 8 years) modifies GH decline. DESIGN: The GH response to maximal exercise on bicycle-ergometer was tested in younger (26-30 years) and older (42-46 years) healthy women. Each age group included 2 subgroups of 10 sedentary and 10 runners, which were compared. The workload was increased at 3 min intervals from time 0 until exhaustion. Subjects with a low maximal capacity (as established in a preliminary test) pedalled for 3-4 min against no workload at the beginning of the test, so that exercises lasted about 15 min in all individuals. RESULTS: At exhaustion, heart rate and systolic pressure were significantly higher in sedentary than in trained subjects, whereas V(O(2)max), blood glucose and plasma lactate levels were similar in all groups. Exercise induced similar GH responses in younger sedentary and exercise-trained subjects and in older exercise-trained subjects, with mean peak levels 7.5 times higher than baseline. In contrast, in older sedentary women peak GH level was only 4.4 times higher than baseline and was significantly lower than in the other groups. CONCLUSION: These data suggest that in women prolonged physical training exerts protective effects against age-dependent decline in GH secretion.

Adrenocorticotropic hormone/cortisol response to physical exercise in abstinent alcoholic patients.

BACKGROUND: Alterations in the hypothalamic-pituitary-adrenal (HPA) axis in alcoholic patients have been reported in various experimental conditions. METHODS: To establish whether alcoholism affects the HPA axis activation during physical exercise, 10 recent abstinent alcoholic patients (age range: 33-45 years; duration of alcohol dependence: range 4-6 years) were tested by exercising on a bicycle ergometer. Ten age-matched healthy nonalcoholic men participated as controls. The workload was gradually increased at 3-minute intervals until exhaustion and lasted about 15 minutes for all subjects. Alcoholic patients were tested at 3 time points, at 4, 6, and 8 weeks after alcohol withdrawal, whereas controls were tested only once. Main outcome measurements were circulating levels of adrenocorticotropic hormone (ACTH) and cortisol and physiological variables during physical exercise [heart rate, blood pressure, ventilation, frequency of breathing, tidal volume, oxygen consumption (VO2), carbon oxide production (VCO2), and respiratory exchange ratio (R)]. RESULTS: Similar basal and exercise-induced changes in physiological variables were observed in controls and alcoholic patients in all tests. Basal levels of ACTH and cortisol were similar in all tests performed on alcoholic patients and on normal controls. In normal subjects, exercise induced a significant increase in plasma ACTH and serum cortisol levels, with peak levels at 20 minutes for ACTH (84% higher than baseline) and at 30 minutes for cortisol (70% higher than baseline). After 4 weeks of abstinence, slight but not significant ACTH/cortisol responses to physical exercise were observed in alcoholic patients (mean peaks were 10 and 18% higher than baseline, respectively, for ACTH and cortisol). By contrast, when the exercise test was repeated after 6 weeks abstinence, ACTH/cortisol levels rose significantly versus baseline (mean peak levels of ACTH and cortisol were 48 and 38% higher than baseline, respectively, for ACTH and cortisol). However, the hormonal responses were significantly lower than in the normal controls. At 8 weeks of abstinence, ACTH/cortisol responses were significantly higher than 2 weeks previously, and were not distinguishable from the increments observed in the normal controls (76 and 68% higher than baseline, respectively, for ACTH and cortisol). CONCLUSIONS: In concurrence with previous reports showing alterations of the HPA axis in the central nervous system in alcohol-dependent subjects, these data show a defect of the neuroendocrine mechanism(s) underlying the ACTH/cortisol response to physical exercise for at least a month after alcohol withdrawal, with reconstitution of a normal hormonal response at 8 weeks.

Antígenos tumorales y fenómenos inmunitarios en neoplasias malignas de estirpe epitelial: detección cualitativa, correlación e interpretación de los hallazgos / Tumoral antigens and immunitary phenomena in malignant neoplasms of epithelial origin

Se estudiaron cuarenta y ocho casos de tumores malignos de origen epitelial (trece del epitelio pavimentoso y treinta y cinco del epitelio glandular). Se realizó la inmunomarcación utilizando la técnica P.A.P. -método indirecto- para detección de alfa-feto proteína y S.P. 1. Se exponen los resultados obtenidos y su correlación con los fenómenos inmunitarios

Colitis por citomegalovirus en el síndrome de inmunodeficiencia adquirida: presentación de 2 casos de autopsia / Colitis by cytomegalovirus in AIDS: report of 2 cases of autopsy

Se presentan 2 casos con autopsia de colitis por CMV en pacientes con SIDA. En ambos casos el cuadro intestinal se manifestó con diarreas y dolores cólicos. La evolución fué de 2 y 5 meses en cada caso, con remisiones. No existió colopatía previa. El caso 1 falleció por infección diseminada por CMV y el caso 2 por TBC miliar caseificante aguda. El caso 1 se hallaron úlceras agudas en ciego e ileon y focos de necrosis en submucosa y capa muscular. En el caso 2 observaron: dilatación del sigma, hemorragia mucosa, úlceras milimetricas y particular fibrosis submucosa en colon transverso. En ambos casos los capilares del fondo de las ulceras, de la mucosa y la submucosa de las zonas marginales, mostraron en su endotelio cuerpos de inclusión viral. Se comparan los hallazgos en estos casos con los de otros casos recientemente publicados

Síndrome de inmunodeficiencia adquirida (SIDA): correlación clinico-patológica en cinco necropsias / Acquired immunodeficiency syndrome (AIDS): correlation clinico-patological in 5 necropsies

EL SIDA es una enfermedad en la que todos los hallazgos parecen indicar que se transmite por via sexual y parenteral. Si bien fue descripto previamente en la comunidad homosexual, luego se extendió a los drogadictos, politransfundidos, bisexuales, a las parejas de los mismos y a los hijos de éstos. El agente etiológico postulado pertenece a la familia de los retrovirus y ha sido designado como HTLV III/LAV. Como consecuencia de la inmunodepresión los pacientes presentan gran variedad de infecciones, algunas de ellas oportunistas y neoplasias no comunes. Es una enfermedad de elevada mortalidad produciéndose el desenlance por la conjunción de los factores mencionados. Se presentan cinco casos de necropsias de SIDA cuyo estudio macro y microscópico mostró las alteraciones sañaladas: 1) depleción linfoide ganglionar en todos los casos; 2) infecciones por tuberculosis, citomegalovirus, hepatitis B y bacterias comunes, y 3) neoplasias-sarcoma de Kaposi - en un caso