Erratum: Formation of a Spin Texture in a Quantum Gas Coupled to a Cavity [Phys. Rev. Lett. 120, 223602 (2018)].

This corrects the article DOI: 10.1103/PhysRevLett.120.223602.

P-Band Induced Self-Organization and Dynamics with Repulsively Driven Ultracold Atoms in an Optical Cavity.

We investigate a Bose-Einstein condensate strongly coupled to an optical cavity via a repulsive optical lattice. We detect a stable self-ordered phase in this regime, and show that the atoms order through an antisymmetric coupling to the P band of the lattice, limiting the extent of the phase and changing the geometry of the emergent density modulation. Furthermore, we find a nonequilibrium phase with repeated intense bursts of the intracavity photon number, indicating nontrivial driven-dissipative dynamics.

Dissipation-Induced Anomalous Multicritical Phenomena.

We explore the influence of dissipation on a paradigmatic driven-dissipative model where a collection of two level atoms interact with both quadratures of a quantum cavity mode. The closed system exhibits multiple phase transitions involving discrete and continuous symmetries breaking and all phases culminate in a multicritical point. In the open system, we show that infinitesimal dissipation erases the phase with broken continuous symmetry and radically alters the model's phase diagram. The multicritical point now becomes brittle and splits into two tricritical points where first- and second-order symmetry-breaking transitions meet. A quantum fluctuations analysis shows that, surprisingly, the tricritical points exhibit anomalous finite fluctuations, as opposed to standard tricritical points arising in ^{3}He-^{4}He mixtures. Our work has direct implications for a variety of fields, including cold atoms and ions in optical cavities, circuit-quantum electrodynamics as well as optomechanical systems.

Formation of a Spin Texture in a Quantum Gas Coupled to a Cavity.

We observe cavity mediated spin-dependent interactions in an off-resonantly driven multilevel atomic Bose-Einstein condensate that is strongly coupled to an optical cavity. Applying a driving field with adjustable polarization, we identify the roles of the scalar and the vectorial components of the atomic polarizability tensor for single and multicomponent condensates. Beyond a critical strength of the vectorial coupling, we infer the formation of a spin texture in a condensate of two internal states from the analysis of the cavity output field. Our work provides perspectives for global dynamical gauge fields and self-consistently spin-orbit coupled gases.

Experimental Determination of Irreversible Entropy Production in out-of-Equilibrium Mesoscopic Quantum Systems.

By making use of a recently proposed framework for the inference of thermodynamic irreversibility in bosonic quantum systems, we experimentally measure and characterize the entropy production rates in the nonequilibrium steady state of two different physical systems-a micromechanical resonator and a Bose-Einstein condensate-each coupled to a high finesse cavity and hence also subject to optical loss. Key features of our setups, such as the cooling of the mechanical resonator and signatures of a structural quantum phase transition in the condensate, are reflected in the entropy production rates. Our work demonstrates the possibility to explore irreversibility in driven mesoscopic quantum systems and paves the way to a systematic experimental assessment of entropy production beyond the microscopic limit.

Sideband cooling of micromechanical motion to the quantum ground state.

The advent of laser cooling techniques revolutionized the study of many atomic-scale systems, fuelling progress towards quantum computing with trapped ions and generating new states of matter with Bose-Einstein condensates. Analogous cooling techniques can provide a general and flexible method of preparing macroscopic objects in their motional ground state. Cavity optomechanical or electromechanical systems achieve sideband cooling through the strong interaction between light and motion. However, entering the quantum regime--in which a system has less than a single quantum of motion--has been difficult because sideband cooling has not sufficiently overwhelmed the coupling of low-frequency mechanical systems to their hot environments. Here we demonstrate sideband cooling of an approximately 10-MHz micromechanical oscillator to the quantum ground state. This achievement required a large electromechanical interaction, which was obtained by embedding a micromechanical membrane into a superconducting microwave resonant circuit. To verify the cooling of the membrane motion to a phonon occupation of 0.34 ± 0.05 phonons, we perform a near-Heisenberg-limited position measurement within (5.1 ± 0.4)h/2π, where h is Planck's constant. Furthermore, our device exhibits strong coupling, allowing coherent exchange of microwave photons and mechanical phonons. Simultaneously achieving strong coupling, ground state preparation and efficient measurement sets the stage for rapid advances in the control and detection of non-classical states of motion, possibly even testing quantum theory itself in the unexplored region of larger size and mass. Because mechanical oscillators can couple to light of any frequency, they could also serve as a unique intermediary for transferring quantum information between microwave and optical domains.

Efficacy and safety of low-dose otelixizumab anti-CD3 monoclonal antibody in preserving C-peptide secretion in adolescent type 1 diabetes: DEFEND-2, a randomized, placebo-controlled, double-blind, multi-centre study.

AIMS: Phase III DEFEND-2 investigated whether otelixizumab (3.1 mg over 8 days) preserved C-peptide secretion in patients with new-onset Type 1 diabetes, focusing on adolescents (12-17 years). METHODS: One hundred and seventy-nine patients (54 adolescents) were randomized to otelixizumab or placebo. The primary endpoint was change in 2-h mixed-meal-stimulated C-peptide area under the curve at month 12. Enrolment was suspended in April 2011 following negative efficacy results from DEFEND-1. DEFEND-2 terminated early after 12 months' efficacy and safety follow-up. RESULTS: Change from baseline C-peptide was not significantly different [∆ = -0.09 nmol/l (95% CI -0.17 to 0; P = 0.051)]. No differential C-peptide effect was seen for otelixizumab in adolescents and more adverse events were reported. CONCLUSIONS: Efficacy and tolerability of otelixizumab was similar to DEFEND-1. The 3.1-mg dose was non-efficacious in adults and adolescents. Further investigation of the mechanism of action seen at higher doses and therapeutic window is required. Clinical Trials Registry No: NCT 00763451.

Decision making: How the past guides the future in frontal cortex.

Our judgments of our environment are often shaped by heuristics and prior experience. New research shows that the resulting biases are encoded, and combined with new sensory input, by groups of neurons in the frontal cortex during decisions under uncertainty.

Brainstem Modulation of Large-Scale Intrinsic Cortical Activity Correlations.

Brain activity fluctuates continuously, even in the absence of changes in sensory input or motor output. These intrinsic activity fluctuations are correlated across brain regions and are spatially organized in macroscale networks. Variations in the strength, topography, and topology of correlated activity occur over time, and unfold upon a backbone of long-range anatomical connections. Subcortical neuromodulatory systems send widespread ascending projections to the cortex, and are thus ideally situated to shape the temporal and spatial structure of intrinsic correlations. These systems are also the targets of the pharmacological treatment of major neurological and psychiatric disorders, such as Parkinson's disease, depression, and schizophrenia. Here, we review recent work that has investigated how neuromodulatory systems shape correlations of intrinsic fluctuations of large-scale cortical activity. We discuss studies in the human, monkey, and rodent brain, with a focus on non-invasive recordings of human brain activity. We provide a structured but selective overview of this work and distil a number of emerging principles. Future efforts to chart the effect of specific neuromodulators and, in particular, specific receptors, on intrinsic correlations may help identify shared or antagonistic principles between different neuromodulatory systems. Such principles can inform models of healthy brain function and may provide an important reference for understanding altered cortical dynamics that are evident in neurological and psychiatric disorders, potentially paving the way for mechanistically inspired biomarkers and individualized treatments of these disorders.

Tagatose, a new antidiabetic and obesity control drug.

A potentially important new drug for treating type 2 diabetes, tagatose, is now in phase 3 clinical trial. The history, development, additional health benefits, mechanisms of action and the potential for the drug are presented in context with a review of the rapidly growing epidemic of type 2 diabetes and treatments for it. An epimer of fructose, the natural hexose tagatose was originally developed by Spherix Incorporated (formerly Biospherics Inc.) as a low-calorie sugar substitute. Only 20% of orally ingested tagatose is fully metabolized, principally in the liver, following a metabolic pathway identical to that of fructose. Following a decade of studies, tagatose became generally recognized as safe for use in foods and beverages under US FDA regulation. The simple sugar is commercially produced by isomerization of galactose, which is prepared from lactose. Early human studies suggested tagatose as a potential antidiabetic drug through its beneficial effects on postprandial hyperglycaemia and hyperinsulinaemia. A subsequent 14-month trial confirmed its potential for treating type 2 diabetes, and tagatose showed promise for inducing weight loss and raising high-density lipoprotein cholesterol, both important to the control of diabetes and constituting benefits independent of the disease. Furthermore, tagatose was shown to be an antioxidant and a prebiotic, both properties cited in the maintenance and promotion of health. No current therapies for type 2 diabetes provide these multiple health benefits. The predominant side effects of tagatose are gastrointestinal disturbances associated with excessive consumption, generally accommodated within 1- to 2-week period. The health and use potentials for tagatose (branded Naturlose((R)) for this use) are given with respect to current type 2 diabetes drugs and markets. Under an FDA-affirmed protocol, Spherix is currently conducting a phase 3 trial to evaluate a placebo-subtracted treatment effect based on a decrease in HbA(1c) levels. Side effects, contraindications and possibly beneficial new findings will be carefully monitored. It is hoped that early results of the trial may become available by mid-2008. If a subsequent NDA is successful, tagatose may fill a major health need.

Biopsychobehavioral model of severe hypoglycemia. II. Understanding the risk of severe hypoglycemia.

OBJECTIVE: To evaluate the clinical/research utility of the biopsycho-behavioral model of severe hypoglycemia in differentiating patients with and without a history of severe hypoglycemia and in predicting occurrence of future severe hypoglycemia. RESEARCH DESIGN AND METHODS: A total of 93 adults with type 1 diabetes (mean age 35.8 years, duration of diabetes 16 +/- 10 years, HbA1 8.6 +/- 1.8%), 42 of whom had a recent history of recurrent severe hypoglycemia (SH) and 51 who did not (NoSH), used a handheld computer for 70 trials during 1 month recording cognitive-motor functioning, symptoms, blood glucose (BG) estimates, judgments concerning self-treatment of BG, actual BG readings, and actual treatment of low BG. For the next 6 months, patients recorded occurrence of severe hypoglycemia. RESULTS: SH patients demonstrated significantly more frequent and extreme low BG readings (low BG index), greater cognitive-motor impairments during hypoglycemia, fewer perceived symptoms of hypoglycemia, and poorer detection of hypoglycemia. SH patients were also less likely to treat their hypoglycemia with glucose and more likely to treat with general foods. Low BG index, magnitude of hypoglycemia-impaired ability to do mental subtraction, and awareness of neuroglycopenia, neurogenic symptoms, and hypoglycemia correlated separately with number of SH episodes in the subsequent 6 months. However, only low BG index, hypoglycemia-impaired ability to do mental subtraction, and awareness of hypoglycemia entered into a regression model predicting future severe hypoglycemia (R2 = 0.25, P < 0.001). CONCLUSIONS: Patients with a history of severe hypoglycemia differed on five of the seven steps of the biopsychobehavioral model of severe hypoglycemia. Helping patients with a recent history of severe hypoglycemia to reduce the frequency of their low-BG events, become more sensitive to early signs of neuroglycopenia and neurogenic symptoms, better recognize occurrence of low BG, and use fast-acting glucose more frequently in the treatment of low BG, may reduce occurrence of future severe hypoglycemia.

The Veterans Affairs Implantable Insulin Pump Study: effect on cardiovascular risk factors.

OBJECTIVE: To determine whether implantable insulin pump (IIP) and multiple-dose insulin (MDI) therapy have different effects on cardiovascular risk factors in insulin-requiring patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A randomized clinical trial was conducted at seven Veterans Affairs medical centers in 121 male patients with type 2 diabetes between the ages of 40 and 69 years receiving at least one injection of insulin per day and with HbA1c, levels of > or =8% at baseline. Weights, blood pressures, insulin use, and glucose monitoring data were obtained at each visit. Lipid levels were obtained at 0, 4, 8, and 12 months, and free and total insulin levels were obtained at 0, 6, and 12 months. All medications being taken were recorded at each visit. RESULTS: No difference in absolute blood pressure, neither systolic nor diastolic, was seen between patients receiving MDI or IIP therapy, but significantly more MDI patients required anti-hypertensive medications. When blood pressure was modeled against weight and time, IIP therapy was significantly better than MDI therapy for systolic blood pressure in patients with BMI <33 and for diastolic blood pressure in patients with BMI >34 kg/m2. Total cholesterol levels decreased in the overall sample, but IIP patients exhibited significantly higher levels than MDI patients. Triglyceride levels increased over time for both groups, with IIP patients having significantly higher levels than patients in the MDI group. BMI was a significant predictor of, and inversely proportional to, HDL cholesterol level. No difference in lipid-lowering drug therapy was seen between the two groups. Free insulin and insulin antibodies tended to decrease in the IIP group as compared with the MDI group. C-peptide levels decreased in both groups. CONCLUSIONS: IIP therapy in insulin-requiring patients with type 2 diabetes has advantages over MDI therapy in decreasing the requirement for antihypertensive therapy and for decreasing total and free insulin and insulin antibodies. Both therapies reduce total cholesterol and C-peptide levels.

Extracranial spinal accessory nerve injury.

Eighty-three consecutive patients with extracranial accessory nerve injury seen over a 12-year period are reviewed. The most common etiology was iatrogenic injury to the nerve at the time of previous surgery. Such operations were usually minor in nature and often related to lymph node or benign tumor removal. Examination usually distinguished winging due to trapezius weakness from that of serratus anterior palsy. Trapezius weakness was seen in all cases. Sternocleidomastoid weakness was unusual. Patients with accessory palsy were evaluated by both clinical and electromyographic studies. Patients who exhibited no clinical or electrical evidence of regeneration were operated on (44 cases). Based on intraoperative nerve action potential studies, 8 lesions in continuity had neurolysis alone. Resection with repair either by end-to-end suture or by grafts was necessary in 31 cases. One case had suture removed from nerve, two had nerve placed into target muscle, and two had more proximal neurotization. Function was usually improved in both operative and nonoperative patients. Related anatomy is discussed.

Neural sheath tumors of major nerves.

Over a 22-year period, operations were performed on 263 patients for 288 primary benign tumors of major peripheral nerves. The tumors included 85 schwannomas, 197 neurofibromas, and six plexiform neurofibromas. Total removal was achieved in 83 of the 85 schwannomas, and 76 of these patients were available for follow-up evaluation. Motor function either improved or was unchanged in 87% of these patients and 85% of those with pain in the distribution of the involved nerve had either total or partial resolution of their symptoms. Of the neurofibromas, 123 occurred in 121 patients without von Recklinghausen's disease. All tumors within this group were completely excised using a fascicular approach to the tumor. Of the 99 patients available for follow-up evaluation, 90% had either improved or unchanged motor function and 88% had partial or complete resolution of pain syndromes. Fifty-nine patients with von Recklinghausen's disease had 80 tumors removed: 74 fusiform tumors (58 of which were completely removed) and six plexiform tumors. Forty-eight of the 58 patients with gross total removal of fusiform tumors were available for follow-up evaluation, of whom 83% had improved or unchanged motor function and 74% had partial or complete resolution of pain syndromes. All six patients with plexiform tumors had progression of symptoms postoperatively. One brachial plexus schwannoma recurred and was re-excised without subsequent recurrence at the 5-year follow-up evaluation. Several incompletely excised plexiform neurofibromas have recurred with a symptomatic presentation.

Intraforaminal repair of plexus spinal nerves by a posterior approach: an experimental study.

Many spinal nerve roots injured due to stretch or other types of lesions are not reparable. Some spinal nerves might be repaired if they could be exposed in their intraforaminal course. A posterior subscapular approach for a more lateral exposure of the brachial plexus was combined with a facetectomy to expose intraforaminal nerves in a series of Macaca rhesus monkeys. This approach exposed a 6- to 10-mm segment of spinal nerve not approachable by a more classic anterior operation. Sural grafts were placed from the dural exit of the spinal nerves to the cord level of the plexus. Nine surviving animals were followed for 36 to 54 months and observed for clinical evidence of return of function. In each animal at least one electromyogram (EMG) was performed. The plexus was then re-exposed and intraoperative nerve action potentials were recorded across graft sites. Evoked muscle action potential and cortical potentials were recorded in six animals. Despite the proximal level of repair, adequate regeneration was shown by clinical, electrical, and histological studies. Functional return was best to the supraspinatus and biceps muscles and to wrist and finger flexors. Clinical recovery was present, but less effective, for deltoid, wrist, and finger extensors and intrinsic muscles of the hand, despite evidence on EMG of reinnervation. Recovery of the infraspinatus muscle was poor. Nerve action potentials could be recorded across each graft site. Reinnervational activity was recorded by EMG and evoked muscle action potential studies in most of the muscles studied, despite the persistence of some denervational changes 3 years or more after injury and repair. Histological studies confirmed the presence of a large number of axons of moderate size and myelination even at the forearm level.

Distinguishing between life-saving and life-sustaining treatments: when the physician and spouse disagree.

There is a fine distinction between life-saving measures and life-sustaining ones. In the case presented below the husband of a wife with cancer did not understand the continuation of life-sustaining treatment after the decision to reject life-saving measures was made. This resulted in a conflict between the husband and physician that placed the nurse, as family advocate, in the middle. The case is followed by an analysis with recommendations on how to handle this type of situation.

The Safe Medical Device Act: nursing implications.

The Safe Medical Device Act places a legal responsibility on health care practitioners to assess and report malfunctioning medical equipment. As a result of this law, the Food and Drug Administration (FDA) will for the first time have direct regulatory authority over hospitals. Today's complex and technological critical care setting requires that the nurse understand the legal and professional responsibilities imposed by this Act.

Durable power of attorney: nursing implications.

Written, witnessed advance directives such as Durable Powers of Attorney and Living Wills communicate patients' care preferences. The critical care nurse must be knowledgeable about these legal documents to be able to effectively uphold the specific care requests. The authors define advance directives and outline the role of the nurse in execution of these directives.

One normal angiogram is not always diagnostic after subarachnoid hemorrhage: case report and review of the literature.

How many angiograms should be obtained after subarachnoid hemorrhage if the first one fails to identify an aneurysm? We recently encountered this common clinical problem: a patient with subarachnoid hemorrhage confirmed by computed tomography required three angiograms to identify an aneurysm at the posterior communicating artery. Review of the literature reveals conflicting recommendations as to proper management of this common and sometimes perplexing problem. Decision-making must be applied on a case-by-case basis, but persistence is probably warranted when the index of suspicion is high.

Roton-type mode softening in a quantum gas with cavity-mediated long-range interactions.

Long-range interactions in quantum gases are predicted to give rise to an excitation spectrum of roton character, similar to that observed in superfluid helium. We investigated the excitation spectrum of a Bose-Einstein condensate with cavity-mediated long-range interactions, which couple all particles to each other. Increasing the strength of the interaction leads to a softening of an excitation mode at a finite momentum, preceding a superfluid-to-supersolid phase transition. We used a variant of Bragg spectroscopy to study the mode softening across the phase transition. The measured spectrum was in very good agreement with ab initio calculations and, at the phase transition, a diverging susceptibility was observed. The work paves the way toward quantum simulation of long-range interacting many-body systems.