AI-based Conversational Agents for Customer Service – A Study of Customer Service Representative’ Perceptions Using TAM 2

This study aimed to identify the various factors that may influence customer service representatives’ perceptions of artificial intelligence (AI)-based conversational agents (CAs) for customer service. By analyzing 180 publications, a conceptual research model is developed for identifying the factors that may influence customer service representatives’ perceptions of AI-based CAs for customer service. The underlying conceptual research model comprises ten factors. The study is grounded in the application of the Technology Acceptance Model 2 (TAM 2) approach. The research model is empirically evaluated with survey data from 128 participants. Our results show that the direct positive effect of subjective norm on customer service representatives’ perception of using AIbased CAs in customer service decreases with increasing experience. Moreover, our results reveal new insights regarding trust. The results of this study provide an overview of the predominant characteristics of the influencing factors of customer service representatives’ perceptions of AI-based CAs for customer service

Segmentation of Lath-Like Structures via Localized Identification of Directionality in a Complex-Phase Steel

In this work, a segmentation approach based on analyzing local orientations and directions in an image, in order to distinguish lath-like from granular structures, is presented. It is based on common image processing operations. A window of appropriate size slides over the image, and the gradient direction and its magnitude inside this window are determined for each pixel. The histogram of all possible directions yields the main direction and its directionality. These two parameters enable the extraction of window positions which represent lath-like structures, and procedures to join these positions are developed. The usability of this approach is demonstrated by distinguishing lath-like bainite from granular bainite in so-called complex-phase steels, a segmentation task for which automated procedures are not yet reported. The segmentation results are in accordance with the regions recognized by human experts. The approach’s main advantages are its use on small sets of images, the easy access to the segmentation process and therefore a targeted adjustment of parameters to achieve the best possible segmentation result. Thus, it is distinct from segmentation using deep learning which is becoming more and more popular and is a promising solution for complex segmentation tasks, but requires large image sets for training and is difficult to interpret

Hollow fibres integrated in a microfluidic cell culture system

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.For in vitro drug screening a modified perfusion micro-bioreactor system with integrated hollow fibres will be demonstrated. This biocompatible system consists of an integrated closed flow circuit that includes reservoirs and pneumatic micro pumps. Additional optical online-monitoring devices allow the observation during the cell cultivation. The embedded hollow fibre system which acts as cell carrier consists of a biodegradable biopolymer. One option to fabricate such 3D structures is the technology of Organ Printing which is realised by an adapted rapid prototyping system entitled 3D Scaffold Printer. With this device specimens consisting of tubes with a diameter smaller than 2 mm can be prepared. It should be possible to cultivate the hollow fibres inside and outside with different kinds of cells and therefore generate models of complex tissues

Urinary Excretion of Cyanidin Glucosides and Glucuronides in Healthy Humans After Elderberry Juice Ingestion

In a pilot study with 6 females and 1 male, the metabolism of various cyanidin glucosides after oral administration of elderberry juice was investigated. The anthocyanin metabolites were detected in urinary excretion. After ingestion of a bolus quantity of 3.57 g total anthocyanins in a 150 mL elderberry juice concentrate, 0.053% of the administered dose was excreted in urine as glucosidically bound cyanidins within the first 5 hours. Only 0.003% of the ingested anthocyanin glucosides was excreted as cyanidin glucuronide, suggesting that this conversion step might be of minor importance in urinary excretion

Automated Micro-PIV measurement in Lab-on-a-Chip systems

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Flow rate and wall shear stress are important parameters for perfused cell culture systems and should be monitored. An easy and non-invasive method is the particle image velocimetry (PIV). In this work PIV was used to characterize a cell culture system with included peristaltic pump. The time-dependent flow profile was measured on several points of the chip for different pumping speeds to figure out which forces are applied to dissolved and adherent cells. The results can be used to improve the developed pump in respect to its layout, the excitation and the position within the chip

A modular in vitro flow model to analyse blood-surface interactions under physiological conditions

Newly developed materials for blood-contacting devices need to undergo hemocompatibility testing to prove compliance with clinical requirements. However, many current in vitro models disregard the influence of flow conditions and blood exchange as it occurs in vivo. Here, we present a flow model which allows testing of blood-surface interactions under more physiological conditions. This modular platform consists of a triple-pump-chip and a microchannel-chip with a customizable surface. Flow conditions can be adjusted individually within the physiological range. A performance test with whole blood confirmed the hemocompatibility of our modular platform. Hemolysis was negligible, inflammation and hemostasis parameters were comparable to those detected in a previously established quasi-static whole blood screening chamber. The steady supply of fresh blood avoids secondary effects by nonphysiological accumulation of activation products. Experiments with three subsequently tested biomaterials showed results similar to literature and our own experience. The reported results suggest that our developed flow model allows the evaluation of blood-contacting materials under physiological flow conditions. By adjusting the occurring wall shear stress, the model can be adapted for selected test conditions

Management of high-risk patients with hypertension and left ventricular hypertrophy in Germany: differences between cardiac specialists in the inpatient and outpatient setting

BACKGROUND: Among patients with hypertension, those with established left ventricular hypertrophy (LVH) represent a high risk cohort with poor prognosis. We aimed to investigate differences in characteristics and health care management of such patients treated as inpatients or outpatients by cardiac specialists. METHODS: Prospective cross-sectional study in patients with hypertension and LVH who were referred to either inpatient care (rehabilitation hospitals) or to outpatient care (cardiology practices). RESULTS: A total of 6358 inpatients (59.6% males; mean age 66.6 years) and 2246 outpatients (59.5% males; mean age 63.2 years) were followed up for a mean of 23 vs. 52 days, respectively. Inpatients compared to outpatients had a significantly higher prevalence of coronary heart disease, history of stroke, renal failure or diabetes. Mean blood pressure of inpatients compared to outpatients was significantly lower both at entry (150/84 vs. 161/93 mmHg) and at end of follow-up (129/75 vs. 139/83 mmHg). After adjustment for baseline blood pressure and a propensity score, differences between out- and inpatients at end of follow-up were 8.0/5.1 mmHg in favour of inpatients. Blood pressure goals as specified by guidelines were not met by 32% of inpatients and 55% of outpatients. CONCLUSION: Inpatients had a higher rate of comorbidities and more advanced atherosclerotic disease than outpatients. Control of hypertension of inpatients was already better on admission than in outpatients, and treatment intensity in this group was also higher during the observation period. While blood pressure lowering was substantial in both groups, there were still a high proportion of patients who did not achieve treatment goals at discharge

Moderate hyperventilation during intravenous anesthesia increases net cerebral lactate efflux

BACKGROUND:: Hyperventilation is known to decrease cerebral blood flow (CBF) and to impair cerebral metabolism, but the threshold in patients undergoing intravenous anesthesia is unknown. The authors hypothesized that reduced CBF associated with moderate hyperventilation might impair cerebral aerobic metabolism in patients undergoing intravenous anesthesia. METHODS:: Thirty male patients scheduled for coronary surgery were included in a prospective, controlled crossover trial. Measurements were performed under fentanyl-midazolam anesthesia in a randomized sequence aiming at partial pressures of carbon dioxide of 30 and 50 mmHg. Endpoints were CBF, blood flow velocity in the middle cerebral artery, and cerebral metabolic rates for oxygen, glucose, and lactate. Global CBF was measured using a modified Kety-Schmidt technique with argon as inert gas tracer. CBF velocity of the middle cerebral artery was recorded by transcranial Doppler sonography. Data were presented as mean (SD). Two-sided paired t tests and one-way ANOVA for repeated measures were used for statistical analysis. RESULTS:: Moderate hyperventilation significantly decreased CBF by 60%, blood flow velocity by 41%, cerebral oxygen delivery by 58%, and partial pressure of oxygen of the jugular venous bulb by 45%. Cerebral metabolic rates for oxygen and glucose remained unchanged; however, net cerebral lactate efflux significantly increased from -0.38 (2.18) to -2.41(2.43) μmol min 100 g. CONCLUSIONS:: Moderate hyperventilation, when compared with moderate hypoventilation, in patients with cardiovascular disease undergoing intravenous anesthesia increased net cerebral lactate efflux and markedly reduced CBF and partial pressure of oxygen of the jugular venous bulb, suggesting partial impairment of cerebral aerobic metabolism at clinically relevant levels of hypocapnia. Copyrigh

Automated universal chip platform for fluorescence based cellular assays

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The advantage of cell based assays used as biosensors is the direct access to hardly obtainable parameters like toxicity, mutagenicity and pharmacological effectiveness. Within the last few years we established a micro fluidic platform including a peristaltic micro pump as well as several valves, manifolds and micro channels [1]. For optical online monitoring the micro fluidic system is bonded to a glass slide. Furthermore the biochip is fixed on an electrically heated support. The pneumatically actuated peristaltic pump as well as the temperature control is performed by a control device. For the fluorescence based online monitoring a robotic guided fluorescence measurement module was developed, which supports the detection of fluorescence in microtiter plates and microfluidic systems. This measurement module allows the fluorescence detection of two different excitation / detection wavelengths (480 / 530 nm and 570 / 620 nm) and was successfully characterised using EGFP and Rhodamine 6G. Additionally three cell based assays with bacterial, yeast and human cells were characterized