Transient Analysis of Analyte Desorption Due to Thermal Cycling with Varying Pulse Duration

This paper introduces heating pulse duration modulation on a chemically sensitive, polymer-coated resonant cantilever platform for analyte discrimination during the desorption phase. As in our previous work, the embedded heaters enable real-time measurements of analyte sorption into the polymer film, without the need for traditional valve systems and reference gases [1-2]. This work particularly looks at the effects of varying pulse lengths on the sensor responses, while holding the heating power constant. A model differential equation is developed for the sensor response based on both the device sensitivity and transient response. This model can then be used together with estimation theory for analyte identification and quantification, even in mixtures

SYSTEM-LEVEL APPROACHES FOR IMPROVING PERFORMANCE OF CANTILEVER-BASED CHEMICAL SENSORS

This work presents the development of different technologies and techniques for enhancing the performance of cantilever-based MEMS chemical sensors. The developed methods address specifically the sensor metrics of sensitivity, selectivity, and stability. Different techniques for improving the quality and uniformity of deposited sorbent polymer films onto MEMS-based micro-cantilever chemical sensors are presented. A novel integrated recess structure for constraining the sorbent polymer layer to a fixed volume with uniform thickness was developed. The recess structure is used in conjunction with localized polymer deposition techniques, such as inkjet printing and spray coating using shadow masking, to deposit controlled, uniform sorbent layers onto specific regions of chemical sensors, enhancing device performance. The integrated recess structure enhances the stability of a cantilever-based sensor by constraining the deposited polymer layers away from high-strain regions of the device, reducing Q-factor degradation. Additionally, the integrated recess structure enhances the sensitivity of the sensor by replacing chemically-inert silicon mass with ‘active’ sorbent polymer mass. Finally, implementation of localized polymer deposition enables the use of sensor arrays, where each sensor in the array is coated with a different sorbent, leading to improved selectivity. In addition, transient signal generation and analysis for mass-sensitive chemical sensing of volatile organic compounds (VOCs) in the gas phase is investigated. It is demonstrated that transient signal analysis can be employed to enhance the selectivity of individual sensors leading to improved analyte discrimination. As an example, elements of a simple alcohol series and elements of a simple aromatic ring series are distinguished with a single sensor (i.e. without an array) based solely on sorption transients. Transient signals are generated by the rapid switching of mechanical valves, and also by thermal methods. Thermally-generated transients utilize a novel sensor design which incorporates integrated heating units onto the cantilever and enables transient signal generation without the need for an external fluidic system. It is expected that the thermal generation of transient signals will allow for future operation in a pulsed mode configuration, leading to reduced drift and enhanced stability without the need for a reference device. Finally, A MEMS-based micro thermal pre-concentration (µTPC) system for improving sensor sensitivity and selectivity is presented. The µTPC enhances sensor sensitivity by amplifying low-level chemical concentrations, and is designed to enable coarse pre-filtering (e.g. for injection into a GC system) by means of arrayed and individually-addressable µTPC devices. The system implements a suspended membrane geometry, enhancing thermal isolation and enabling high temperature elevations even for low levels of heating power. The membranes have a large surface area-to-volume ratio but low thermal mass (and therefore, low thermal time constant), with arrays of 3-D high aspect-ratio features formed via DRIE of silicon. Integrated onto the membrane are sets of diffused resistors designed for performing thermal desorption (via joule heating) and for measuring the temperature elevation of the device due to the temperature-dependent resistivity of doped silicon. The novel system features integrated real-time chemical sensing technology, which allows for reduced sampling time and a reduced total system dead volume of approximately 10 µL. The system is capable of operating in both a traditional flow-through configuration and also a diffusion-based quasi-static configuration, which requires no external fluidic flow system, thereby enabling novel measurement methods and applications. The ability to operate without a forced-flow fluidic system is a distinct advantage and can considerably enhance the portability of a sensing system, facilitating deployment on mobile airborne platforms as well as long-term monitoring stations in remote locations. Initial tests of the system have demonstrated a pre-concentration factor of 50% for toluene.Ph.D

In-Plane Vibration of Hammerhead Resonators for Chemical Sensing Applications

Thermally excited and piezoresistively detected in-plane cantilever resonators have been previously demonstrated for gas- and liquid-phase chemical and biosensing applications. In this work, the hammerhead resonator geometry, consisting of a cantilever beam supporting a wider semicircular “head”, vibrating in an in-plane vibration mode, is shown to be particularly effective for gas-phase sensing with estimated limits of detection in the sub-ppm range for volatile organic compounds. This paper discusses the hammerhead resonator design and the particular advantages of the hammerhead geometry, while also presenting mechanical characterization, optical characterization, and chemical sensing results. These data highlight the distinct advantages of the hammerhead geometry over other cantilever designs

Point of care coagulometry in prehospital emergency care: an observational study

Background: Haemostatic impairment can have a crucial impact on the outcome of emergency patients, especially in cases of concomitant antithrombotic drug treatment. In this prospective observational study we used a point of care (POC) coagulometer in a prehospital physician-based emergency medical system in order to test its validity and potential value in the treatment of emergency patients. Methods: During a study period of 12 months, patients could be included if venous access was mandatory for further treatment. The POC device CoaguChek® was used to assess international normalized ratio (INR) after ambulance arrival at the scene. Results were compared with in-hospital central laboratory assessment of INR. The gain of time was analysed as well as the potential value of POC testing through a questionnaire completed by the responsible prehospital emergency physician. Results: A total of 103 patients were included in this study. POC INR results were highly correlated with results of conventional assessment of INR (Bland-Altman-bias: 0.014). Using a cutoff value of INR >1.3, the device’s sensitivity to detect coagulopathy was 100 % with a specificity of 98.7 %. The median gain of time was 69 min. Treating emergency physicians considered the value of prehospital POC INR testing ‘high’ in 9 % and ‘medium’ in 21 % of all patients. In patients with tracer diagnosis ‘neurology’, the value of prehospital INR assessment was considered ‘high’ or ‘medium’ (63 %) significantly more often than in patients with non-neurological tracer diagnoses (24 %). Conclusions: Assessment of INR through a POC coagulometer is feasible in prehospital emergency care and provides valuable information on haemostatic parameters in patients. Questionnaire results suggest that POC INR testing may present a valuable technique in selected patients. Whether this information translates into an improved management of respective patients has to be evaluated in further studies

The Development and Initial Validation of a Measure of Coaching Behaviors in a Sample of Soldiers Under Training

In this article we outline a model of coaching that is conceptually grounded in workplace and sport coaching literature and present 2 studies conducted to test this model: the extent that coaching behaviors are present in a military training setting, and their association with performance-related outcomes. Following an extensive review of literature and rigorous development and validation procedures the 28-item Military Coaching Behavior Scale was tested. The measure showed good content and predictive validity for 2 dependent variables (satisfaction and resilience). We concluded that the Military Coaching Behavior Scale offers a psychometrically sound, brief, and easy-to-administer measure of high-performance coaching behavior

Cultural Heritage and Climate Change: New challenges and perspectives for research

JPI Cultural Heritage & JPI ClimateCollaboration between the two Joint Programming Initiatives “Cultural Heritage and Global Change” (JPI CH), and “Connecting Climate Knowledge for Europe” (JPI Climate) began in 2019 and led to the organisation of a joint workshop a year later. Following the recommendations in the workshop report, an expert working group was set up to scope research gaps and opportunities at the interface of cultural heritage and climate change, culminating in the publication of this White Paper. This strategic document is expected to support the two JPIs to generate policy-relevant research outcomes.Peer reviewe

Role of the Arabidopsis PIN6 auxin transporter in auxin homeostasis and auxin-mediated development

Plant-specific PIN-formed (PIN) efflux transporters for the plant hormone auxin are required for tissue-specific directional auxin transport and cellular auxin homeostasis. The Arabidopsis PIN protein family has been shown to play important roles in developmental processes such as embryogenesis, organogenesis, vascular tissue differentiation, root meristem patterning and tropic growth. Here we analyzed roles of the less characterised Arabidopsis PIN6 auxin transporter. PIN6 is auxin-inducible and is expressed during multiple auxin–regulated developmental processes. Loss of pin6 function interfered with primary root growth and lateral root development. Misexpression of PIN6 affected auxin transport and interfered with auxin homeostasis in other growth processes such as shoot apical dominance, lateral root primordia development, adventitious root formation, root hair outgrowth and root waving. These changes in auxin-regulated growth correlated with a reduction in total auxin transport as well as with an altered activity of DR5-GUS auxin response reporter. Overall, the data indicate that PIN6 regulates auxin homeostasis during plant development.Christopher I. Cazzonelli, Marleen Vanstraelen, Sibu Simon, Kuide Yin, Ashley Carron-Arthur, Nazia Nisar, Gauri Tarle, Abby J. Cuttriss¤, Iain R. Searle, Eva Benkova, Ulrike Mathesius, Josette Masle, Jiří Friml, Barry J. Pogso

Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes

CMB-S4

We describe the stage 4 cosmic microwave background ground-based experiment CMB-S4