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1.
Phys Rev Lett ; 128(6): 063401, 2022 Feb 11.
Article in English | MEDLINE | ID: mdl-35213182

ABSTRACT

We show that ultradilute quantum liquids can be formed with ultracold bosonic dipolar atoms in a bilayer geometry. Contrary to previous realizations of ultradilute liquids, there is no need for stabilizing the system with an additional repulsive short-range potential. The advantage of the proposed system is that dipolar interactions on their own are sufficient for creation of a self-bound state and no additional short-range potential is needed for the stabilization. We perform quantum Monte Carlo simulations and find a rich ground-state phase diagram that contains quantum phase transitions between liquid, solid, atomic gas, and molecular gas phases. The stabilization mechanism of the liquid phase is consistent with the microscopic scenario in which the effective dimer-dimer attraction is balanced by an effective three-dimer repulsion. The equilibrium density of the liquid, which is extremely small, can be controlled by the interlayer distance. From the equation of state, we extract the spinodal density, below which the homogeneous system breaks into droplets. Our results offer a new example of a two-dimensional interacting dipolar liquid in a clean and highly controllable setup.

2.
Sci Rep ; 11(1): 19437, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34593895

ABSTRACT

A halo is an intrinsically quantum object defined as a bound state of a spatial size which extends deeply into the classically forbidden region. Previously, halos have been observed in bound states of two and less frequently of three atoms. Here, we propose a realization of halo states containing as many as six atoms. We report the binding energies, pair correlation functions, spatial distributions, and sizes of few-body clusters composed by bosonic dipolar atoms in a bilayer geometry. We find two very distinct halo structures, for large interlayer separation the halo structure is roughly symmetric and we discover an unusual highly anisotropic shape of halo states close to the unbinding threshold. Our results open avenues of using ultracold gases for the experimental realization of halos composed by atoms with dipolar interactions and containing as many as six atoms.

3.
Rev. osteoporos. metab. miner. (Internet) ; 7(1): 20-22, ene.-mar. 2015. tab
Article in Spanish | IBECS | ID: ibc-137641

ABSTRACT

La hipercalcemia hipocalciúrica familiar (HHF) constituye una causa poco común de hipercalcemia. Su prevalencia se estima que es de 1:78.000 personas. Mostramos un caso con presentación atípica con confirmación mediante diagnóstico genético. Se trata de una mujer de 74 años con osteoporosis remitida al servicio de Endocrinología por sospecha de hiperparatiroidismo primario (HPTP). Presentaba una hormona paratiroidea (PTH) elevada (96,3 pg/ml-límites normales (LN): 15-65 pg/ml) con niveles de calcio, fósforo y magnesio normales, además de una calciuria elevada. Posteriormente presentó cifras de PTH normales, niveles de calcio elevados junto con calciurias normales-elevadas. El cociente aclaramiento de calcio/aclaramiento de creatinina (CCCR, en mmol/l) osciló entre 0,011-0,02 mmol/l. El CCCR < 0,01 es sugestivo de HHF, y el CCCR > 0,02 de HPTP; este cociente se ve limitado en el rango entre 0,01-0,02 mmol/l, motivo por el que se justifica solicitar la prueba genética en todos los pacientes con PTH normales o alt as, hipercalcemia y CCCR < 0,02, requisitos que cumplía nuestro caso índice (AU)


Familial hypocalciuric hypercalcemia (FHH) is an uncommon cause of hypercalcemia. Its prevalence is estimated to be 1:78,000 people. We describe a case with atypical presentation confirmed by genetic diagnosis. This is a case of a woman of 74 years of age with osteoporosis referred to the endocrinology service with suspected primary hyperparathyroidism (HPTP). She presented with a high level of parathyroid hormone (96.3 pg/ml, normal limits (NL): 15-65 pg/ml), with normal levels of calcium, phosphorus and magnesium, as well as a raised level of calciuria. She subsequently presented with normal levels of PTH, raised levels of calcium, combined with normal -high calciuria. The calcium/creatinine clearance ratio (CCCR, in mmol/l) varied between 0.011 and 0.02 mmol/l. A CCCR < 0.01 is suggestive of FHH, and a CCCR > 0.02, of HPTP. This ratio is within the range between 0.01 and 0.02 mmol/l, a reason which justifies requesting a genetic test in all patients with normal or high PTH, hypercalcemia and CCCR < 0.02, requirements which our index case meets (AU)


Subject(s)
Aged , Female , Humans , Hypercalcemia/diagnosis , Calcium/urine , Osteoporosis, Postmenopausal/complications , Hyperparathyroidism/diagnosis , Diagnosis, Differential , Genetic Predisposition to Disease
4.
Obes Surg ; 25(3): 575-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25589020

ABSTRACT

BACKGROUND: Bariatric surgery constitutes the most effective treatment for severely obese type 2 diabetic patients. Exenatide is a glucagon-like peptide 1 receptor agonist that can improve glycemic control and cause weight loss in patients with type 2 diabetes. Clinical experience with exenatide in obese patients with type 2 diabetes waiting for bariatric surgery has not been reported. The aim of the study was to evaluate, in clinical practice, weight and metabolic effects of exenatide (after 3 and 6 months) in patients with type 2 diabetes and obesity waiting for bariatric surgery. METHODS: A total of 100 diabetic adult subjects with a BMI ≥ 35 kg/m(2) were included. Primary endpoints were changes in weight and HbA1c after 6 months of treatment. Secondary endpoints were changes from baseline of a variety of clinical measures (triglycerides levels, blood pressure, and waist circumference). Data were analyzed at 3 and 6 months of follow-up. RESULTS: Treatment for 6 months with exenatide decreased significantly body weight (-12.5 kg) and waist circumference (-13 cm). Twenty percent of patients reduced their BMI under 35 kg/m(2) and significantly improved their metabolic profile (HbA1c <7 %). Significant and maintained decreases in HbA1c of 1 % were observed in the 3 and 6 months cohorts. Triglycerides levels and blood pressure also decreased from baseline to the end of the study. Treatment was discontinued in 19 % of patients mainly due to drug inefficacy (6 %) or adverse events (4 %). CONCLUSIONS: Exenatide twice daily (BID) leads to early, robust, and significant weight loss in a subset of patients with diabetes and severe obesity before bariatric surgery. Clinical trials are needed to confirm the benefits of GLP-1 agonists in type 2 diabetic obese patients or high-risk super-obese patients waiting for bariatric surgery.


Subject(s)
Bariatric Surgery , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Obesity, Morbid/drug therapy , Peptides/therapeutic use , Venoms/therapeutic use , Adult , Blood Glucose/metabolism , Blood Pressure , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/etiology , Exenatide , Female , Glucagon-Like Peptide 1/agonists , Humans , Male , Middle Aged , Obesity, Morbid/complications , Obesity, Morbid/surgery , Prospective Studies , Treatment Outcome , Waist Circumference , Weight Loss
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