A Double Well Interferometer on an Atom Chip

Radio-Frequency coupling between magnetically trapped atomic states allows to create versatile adiabatic dressed state potentials for neutral atom manipulation. Most notably, a single magnetic trap can be split into a double well by controlling amplitude and frequency of an oscillating magnetic field. We use this to build an integrated matter wave interferometer on an atom chip. Transverse splitting of quasi one-dimensional Bose–Einstein condensates over a wide range from 3 to 80 μm is demonstrated, accessing the tunnelling regime as well as completely isolated sites. By recombining the two split BECs in time of flight expansion, we realize a matter wave interferometer. The observed interference pattern exhibits a stable relative phase of the two condensates, clearly indicating a coherent splitting process. Furthermore, we measure and control the deterministic phase evolution throughout the splitting process. RF induced potentials are especially suited for integrated micro manipulation of neutral atoms on atom chips: designing appropriate wire patterns enables control over the created potentials to the (nanometer) precision of the fabrication process. Additionally, hight local RF amplitudes can be obtained with only moderate currents. This new technique can be directly implemented in many existing atom chip experiments.     

Unobtrusive physiological monitoring in an airplane seat

Air travel has become the preferred mode of long-distance transportation for most of the world’s travelers. People of every age group and health status are traveling by airplane and thus the airplane has become part of our environment, in which people with health-related limitations need assistive support. Since the main interaction point between a passenger and the airplane is the seat, this work presents a smart airplane seat for measuring health-related signals of a passenger. We describe the design, implementation and testing of a multimodal sensor system integrated into the seat. The presented system is able to measure physiological signals, such as electrocardiogram, electrodermal activity, skin temperature, and respiration. We show how the design of the smart seat system is influenced by the trade-off between comfort and signal quality, i.e. incorporating unobtrusive sensors and dealing with erroneous signals. Artifact detection through sensor fusion is presented and the working principle is shown with a feasibility study, in which normal passenger activities were performed. Based on the presented method, we are able to identify signal regions in which the accuracies for detecting the heart- and respiration-rate are 88 and 82%, respectively, compared to 40 and 76% without any artifact removal.     

Partner violence before and after couples-based alcoholism treatment for female alcoholic patients.

This study examined partner violence before and in the 1st and 2nd year after behavioral couples therapy (BCT) for 103 married or cohabiting women seeking alcohol dependence treatment and their male partners; it used a demographically matched nonalcoholic comparison sample. The treatment sample received M = 16.7 BCT sessions over 5–6 months. Follow-up rates for the treatment sample at Years 1 and 2 were 88% and 83%, respectively. In the year before BCT, 68% of female alcoholic patients had been violent toward their male partner, nearly 5 times the comparison sample rate of 15%. In the year after BCT, violence prevalence decreased significantly to 31% of the treatment sample. Women were classified as remitted after treatment if they demonstrated abstinence or minimal substance use and no serious consequences related to substance use. In Year 1 following BCT, 45% were classified as remitted, and 49% were classified as remitted in Year 2. Among remitted patients in the year after BCT, violence prevalence of 22% did not differ from the comparison sample and was significantly lower than the rate among relapsed patients (38%). Results for male-perpetrated violence and for the 2nd year after BCT were similar to the 1st year. Results supported predictions that partner violence would decrease after BCT and that clinically significant violence reductions to the level of a nonalcoholic comparison sample would occur for patients whose alcoholism was remitted after BCT. These findings replicate previous research among men with alcoholism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hybrid heating system for increased energy efficiency and flexible control of low temperature heat

This study presents the evaluation of functionality and potential of a hybrid heating system (H²S) prototype. This technology is designed for retrofitting thermal treatment plants to use hot water (HW) and steam in controlled ratios. In the food industry, steam with a temperature above 140 °C usually indirectly supplies the thermal production processes, but most of them only require temperatures below 100 °C. Total site heat integration is applied on a cheese and whey powder plant to show the potential for low-temperature heat (below 100 °C) that could be supplied more appropriately by hot water cogeneration, heat recovery and heat pumps. These low-temperature heat sources can only be combined with the rigid steam system if the demand structure is changed to a hybrid use of HW and steam. The H²S increases the energy efficiency and flexibility by integrating low-temperature heat and responding to sudden changes in the demand and supply structure, like demand response strategies on intermittent renewable energies and the changing availability of HW and steam. The technical implementation is realised by a hydraulic interconnection of heat exchangers and valves. A smart control algorithm acutely determines the share of HW and steam. Prerequisite for functional verification on a laboratory scale is a hardware-in-the-loop (HIL) testbed, in which load profiles and relevant process parameters are passed in real time between hardware components and simulation. The results show that the H²S is a feasible solution for maintaining product quality and safety while also increasing energy efficiency and energy flexibility.     

Simulation of complex movements using artificial neural networks

A simulated network for controlling a six-legged, insect-like walking system is proposed. The network contains internal recurrent connections, but important recurrent connections utilize the loop through the environment. This approach leads to a subnet for controlling the three joints of a leg during its swing which is arguably the simplest possible solution. The task for the stance subnet appears more difficult because the movements of a larger and varying number of joints (9-18: three for each leg in stance) have to be controlled such that each leg contributes efficiently to support and propulsion and legs do not work at cross purposes. Already inherently non-linear, this task is further complicated by four factors: 1) the combination of legs in stance varies continuously. 2) during curve walking, legs must move at different speeds, 3) on compliant substrates, the speed of the individual legs may vary unpredictably, and 4) the geometry of the system may vary through growth and injury or due to non-rigid suspension of the joints. This task appears to require some kind of "motor intelligence". We show that an extremely decentralized, simple controller, based on a combination of negative and positive feedback at the joint level, copes with all these problems by exploiting the physical properties of the system.     

Family-of-origin maltreatment, posttraumatic stress disorder symptoms, social information processing deficits, and relationship abuse perpetration.

In this study, the authors examined the interrelations among family-of-origin maltreatment variables, posttraumatic stress disorder (PTSD) symptoms, social information processing deficits, and male-to-female psychological and physical intimate relationship abuse perpetration in adulthood among a community sample of 164 men and their partners. In bivariate analyses, higher family-of-origin childhood parental rejection was associated with the perpetration of psychological and physical abuse in adulthood, and childhood exposure to interparental violence was also associated with adult psychological abuse perpetration. Structural equation modeling analyses indicated that when childhood variables and other study variables were considered together, only childhood parental rejection was associated with the abuse perpetration outcomes, and these effects were indirect through PTSD symptoms and social information processing deficits. Results indicate a need for further investigation into the mechanisms accounting for the impact of early maltreatment on the development of abusive intimate relationship behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Heats of Hydrolysis and Formation of Potassium Borohydride

The heat of reaction of potassium borohydride with 0.060 molal HCl has been measured by solution calorimetry. The heat of solution of the hydrolysis products has also been measured and combined with certain literature values to calculate the process: KBH4(c)+HCl(g)+3H2O(liq)→KCl(c)+H3BO3(c)+4H2(g),ΔH°(25°C)=−354.06±1.84kj/mole(−84.62±0.44kcal/mole).A combination of this value with literature values for the heats of formation of HCl(g), H₂O(liq), KCl(c), and H₃BO₃(c) gives for KBH₄(c): ΔHf°(25°C) = ?228.86 ± 2.30 kj/mole(?54.70 ± 0.55 kcal/mole).Other data on the heats of formation of the alkali-metal borohydrides are discussed briefly.     

Rheological properties and structure of step‐ and chain‐growth gels concentrated above the overlap concentration

Cross‐linked polymeric gels are widely used in applications ranging from biomaterial scaffolds to additives in enhanced oil recovery. Despite this, fundamental understanding of the effect of polymer concentration and reaction mechanism on the scaffold structure is lacking. We measure scaffold properties and structure during gelation using multiple particle tracking microrheology. To determine the effect of concentration, we measure gelation as polymer interactions are increased in the backbone precursor solution: below, at and above the overlap concentration, . To determine structural changes due to the gelation mechanism, we measure gelation between the same polymers undergoing both step‐ and chain‐growth reactions using self‐assembling maleimide:thiol and photo‐initiated acrylate:thiol chemistries, respectively. We determine the critical relaxation exponent, n, a measure of structure. n decreases with increasing concentration, indicating a change from a percolated ( ) to a tightly cross‐linked network ( ). The gelation mechanism does not have a measurable effect on the scaffold structure. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3168–3176, 2018     

Transition metal doped cadmium manganese telluride: A new material for tunable mid-infrared lasing

Relatively new materials for mid-infrared tunable lasing using chromium-doped Cd_1-xMn_xTe and cobalt-doped Cd_1-xMn_xTe have been developed. Previously, ZnS and ZnSe were used as host materials for chromium to produce mid-infrared (MIR) lasing. Compared to these materials, large diameter CdMnTe is easier to grow (using the Bridgman technique) and can be made more homogeneous. Moreover, the ternary nature of Cd_1-xMn_xTe offers the unique opportunity to optimize the optical properties of the material through variation of chemical composition and lattice parameter. Using Cd_0.55Mn_0.45Te:Cr, we have demonstrated room temperature lasing from 2.1 to 3.0 m, and we have demonstrated quasi-continuous wave (cw) lasing. To our knowledge, the observed tuning range (∼840 nm) of Cr²⁺:Cd_0.55Mn_0.45Te is the largest ever reported from a transition metal ion laser. Furthermore, this is the first time that a room temperature quasi-cw laser operating at 3 m has been demonstrated using this type of material. Also, preliminary work on Cd_0.55Mn_0.45Te:Co indicates its potential for tunable mid-infrared lasing around 3600 nm at cryogenic temperatures. Results from inductively coupled plasma mass spectrometry (ICP-MS), which determine the concentration of dopant that has been incorporated in to the host lattice, will be reported, as will the materials characterization and lasing results. The processing issues for optimizing the laser performance in these material systems will also be discussed.     

Control of Walking in the Stick Insect: From Behavior and Physiology to Modeling

Classical engineering approaches to controlling a hexapod walker typically involve a central control instance that implements an abstract optimal gait pattern and relies on additional optimization criteria to generate reference signals for servocontrollers at all the joints. In contrast, the gait of the slow-walking stick insect apparently emerges from an extremely decentralized architecture with separate step pattern generators for each leg, a strong dependence on sensory feedback, and multiple, in part redundant, primarily local interactions among the step pattern generators. Thus, stepping and step coordination do not reflect an explicit specification based on a global optimization using a representation of the system and its environment; instead they emerge from a distributed system and from the complex interaction with the environment. A similarly decentralized control at the level of single leg joints also may explain the control of leg dynamics. Simulations show that negative feedback for control of body height and walking direction combined with positive feedback for generation of propulsion produce a simple, extremely decentralized system that can handle a wide variety of changes in the walking system and its environment. Thus, there is no need for a central controller implementing global optimization. Furthermore, physiological results indicate that the nervous system uses approximate algorithms to achieve the desired behavioral output rather than an explicit, exact solution of the problem. Simulations and implementation of these design principles are being used to test their utility for controlling six-legged walking machines.