A Portable Wireless Particulate Sensor System for Continuous Real-Time Environmental Monitoring

Airborne particulate matter has been shown to be associated with morbidity and mortality, and may interfere with certain sensitive experiment. Understanding the levels and movements of particulate matter in an enclosed space can lead to a reduction in the impact of this material on health and experimental results. A system of environmental sensors including particulate matter, selected gasses, humidity, temperature, and pressure can be used to assist in tracking air movement, providing real-time mapping of potential contaminants as they move through a space. In this paper we present a system that is capable of sensing these environmental factors, collecting data from multiple dispersed nodes and presenting the aggregated information in real-time. The highly modular system is based on a flexible and scalable framework developed for use in aircraft cabin environments. Use of this framework enables the deployment of a custom suite of sensors with minimal development effort. Individual nodes communicate using a self-organizing mesh network and can be powered from a variety of sources, bringing a high level of flexibility in the arrangement and distribution of the sensor array. Sensor data is transmitted to a coordinator node, which then passes the time-correlated information to a server-hosted database through a choice of wired or wireless networks. Presentation software is used to either monitor the real-time data stream, or to extract records of interest from the database. A reference implementation has been created for the National Institutes of Health consisting of a custom optical particle counter and off-the-shelf sensors for CO2, CO, temperature, humidity, pressure, and acoustic noise. The total environmental sensing system provides continuous, real-time data in a readable format that can be used to analyze ambient air for events of interest

Src Dependent Pancreatic Acinar Injury Can Be Initiated Independent of an Increase in Cytosolic Calcium

Several deleterious intra-acinar phenomena are simultaneously triggered on initiating acute pancreatitis. These culminate in acinar injury or inflammatory mediator generation in vitro and parenchymal damage in vivo. Supraphysiologic caerulein is one such initiator which simultaneously activates numerous signaling pathways including non-receptor tyrosine kinases such as of the Src family. It also causes a sustained increase in cytosolic calcium- a player thought to be crucial in regulating deleterious phenomena. We have shown Src to be involved in caerulein induced actin remodeling, and caerulein induced changes in the Golgi and post-Golgi trafficking to be involved in trypsinogen activation, which initiates acinar cell injury. However, it remains unclear whether an increase in cytosolic calcium is necessary to initiate acinar injury or if injury can be initiated at basal cytosolic calcium levels by an alternate pathway. To study the interplay between tyrosine kinase signaling and calcium, we treated mouse pancreatic acinar cells with the tyrosine phosphatase inhibitor pervanadate. We studied the effect of the clinically used Src inhibitor Dasatinib (BMS-354825) on pervanadate or caerulein induced changes in Src activation, trypsinogen activation, cell injury, upstream cytosolic calcium, actin and Golgi morphology. Pervanadate, like supraphysiologic caerulein, induced Src activation, redistribution of the F-actin from its normal location in the sub-apical area to the basolateral areas, and caused antegrade fragmentation of the Golgi. These changes, like those induced by supraphysiologic caerulein, were associated with trypsinogen activation and acinar injury, all of which were prevented by Dasatinib. Interestingly, however, pervanadate did not cause an increase in cytosolic calcium, and the caerulein induced increase in cytosolic calcium was not affected by Dasatinib. These findings suggest that intra-acinar deleterious phenomena may be initiated independent of an increase in cytosolic calcium. Other players resulting in acinar injury along with the Src family of tyrosine kinases remain to be explored. © 2013 Mishra et al

Structural Transition Produced by Electric Fields in Aqueous Sodium Deoxyribonucleate

It was found that the birefringence of aqueous solutions of sodium DNA is anomalous when electric fields of high intensity (≥10(4) v/cm) are applied. The magnitude of the birefringence first rose upon application of the orienting pulse, then fell as the field was sustained above a critical value. The occurrence of the effect depended upon macromolecular and electrolyte concentrations. Upon removal of the field, the birefringence was rapidly restored and then it decayed with an increase of the reorientational relaxation times, relative to those observed below the critical field. It is proposed that the electric field may cause aggregation of the macromolecules and then produce a structural transition concomitant with the electric field orientation effect. This transition may correspond to the “B” ⇌ “A” structures identified in x-ray studies, or to a “B” ⇌ “V” structure change, where “V” is a postulated new helical form stabilized by cooperative interactions of base and dipoles in the electric field. Field induced transitions of this type would be of interest in connection with molecular mechanisms of transport through membranes, nerve impulse transmission, or information storage