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Hispanics are the majority ethnic population in Puerto Rico where we reviewed charts of 109 hospitalized COVID-19 patients to better understand demographic and clinical characteristics of COVID-19 and determine risk factors for poor outcomes. Eligible medical records of hospitalized patients with confirmed COVID-19 illnesses were reviewed at four participating hospitals in population centers across Puerto Rico and data were abstracted that described the clinical course, interventions, and outcomes. We found hospitalized patients had a median of 3 underlying conditions with obesity and diabetes as the most frequently reported conditions. Intensive care unit (ICU) admission occurred among 28% of patients and 18% of patients died during the hospitalization. Patients 65 or older or with immune deficiencies had a higher risk for death. Common symptoms included cough, dyspnea, and fatigue; less than half of patients in the study reported fever which was less frequent than reported elsewhere in the literature. It is important for interventions within Hispanic communities to protect high-risk groups.

The aim of this work was to study the effect of the carbon source (glycerol, sucrose, glucose or a sucrose/glucose mixture) on the production of the anti LDL (-) single-chain variable fragment (scFv) by the recombinant Pichia pastoris SMD 1168 strain as well as on the cell size. The use of glucose as a carbon source in the growth phase led to a remarkable increase in cell size compared with glycerol, while the smallest cells were obtained with sucrose likely due to the occurrence of an energetic stress. The scFv concentration seemed to be related to cell number rather than to cell concentration, which in its turn showed no significant dependence on the carbon source. Yeast cells grown on sucrose had a mean diameter (0.736 ± 0.097 μm) about 35% shorter than those grown on glucose and allowed for the highest final concentration of the scFv antibody fragment (93.7 ± 0.2 mg/L). These results demonstrate that sucrose is the best carbon source for the expression of such an antibody fragment by the recombinant P. pastoris strain, which may be very useful for the diagnostic analysis of the so-called "bad cholesterol".

Accurate measurements of ozone in the upper tropical troposphere and lower stratosphere (UTLS) are challenging for most measuring systems, yet of great importance for the understanding of the chemical and dynamical processes in this region.Balloon-borne observations using Electrochemical Concentration Cell (ECC) ozone sondes are the most widely used in situ technology to measure vertical profiles of ozone in networks such as the Southern Hemisphere ADditional Ozonesondes (SHADOZ) network of tropical and subtropical ozone sonde stations.The tropical upper troposphere and the layers of near-zero ozone within the ozone hole are most sensitive to processing and preparation variations that may affect the accuracy and possibly trend estimates of ozone in low ozone regions. It is now appreciated that the complex chemistry within the ECC used to detect ozone exhibits two different time constants (τfast≈20 s, τslow≈25 min), which modify the response of the ECC during a profile. Although not well understood, the chemistry of the slow reaction is likely to represent what has conventionally been assumed a constant “background current”. The fast reaction causes some delay in the response of the ECC to changes in the vertical profile of ozone. Here we show how correcting for both improves the estimate of the lowest ozone concentration in the upper troposphere as well as the steepness of the gradient in the transition into the stratosphere. The steady state bias, which describes the contribution of the slow reaction, is the largest source of uncertainty overall; the response time of the fast reaction dominates the uncertainty in the region of the sharp gradient of ozone above the tropopause.

Biotechnology advances have allowed bacteria, yeasts, plants, mammalian and insect cells to function as heterologous protein expression systems. Recently, microalgae have gained attention as an innovative platform for recombinant protein production, due to low culture media cost, compared to traditional systems, as well as the fact that microalgae such as Chlamydomonas reinhardtii are considered safe (GRAS) by the Food and Drug Administration (FDA). Previous studies showed that recombinant protein production in traditional platforms by semicontinuous process increased biomass and bio product productivity, when compared to batch process. As there is a lack of studies on semicontinuous process for recombinant protein production in microalgae, the production of recombinant mCherry fluorescent protein was evaluated by semicontinuous cultivation of Chlamydomonas reinhardtii in bubble column photobioreactor. This semicontinuous cultivation process was evaluated in the following conditions: 20%, 40%, and 60% culture portion withdrawal. The highest culture withdrawal percentage (60%) provided the best results, as an up to 161% increase in mCherry productivity (454.5 RFU h-1 - Relative Fluorescence Unit h-1 ), in comparison to batch cultivation (174.0 RFU h-1 ) of the same strain. All cultivations were carried out for 13 days, at pH 7, temperature 25°C and, by semicontinuous process, two culture withdrawals were taken during the cultivations. Throughout the production cycles, it was possible to obtain biomass concentration up to 1.36 g L-1 .

Injection molding of boron carbide (B4C) slurries affords the production of complex-shaped personal armor. To injection mold, however, requires preparation of a well dispersed, flowable suspension with >45 vol% B4C loadings to reduce porosity that must be removed during sintering. In the present study, the preparation of highly-loaded B4C suspensions is investigated using zeta potential and rheological measurements, varying dispersant type, molecular weight, and amount. Of those dispersants investigated, polyethylenimine (PEI) with a molecular weight of 25,000 g/mol was found to produce suspensions with up to 56 vol% B4C and the requisite rheological properties suitable for injection molding. A PEI concentration of 1.83 mg/m2 was established as the appropriate to produce highly-loaded B4C suspensions. The effect of a prior B4C powder treatment (ethanol washed or attrition milled) on rheological properties of the suspensions was also investigated. The PEI was completely burned out in argon, nitrogen, and air at 450 °C.

International audience; We present a new design of a Vertical Cavity Surface Emitting Laser (VCSEL) emitting in the Mid Infrared (MIR) spectral range. This new design relies on three key elements: An Interband Cascade (IC) active region, a hybrid structure with a dielectric and a semiconductor Bragg mirror and an arsenide layer for the optical and electric confinement (Fig. 1). Vertical cavity surface emitting lasers (VCSELs) are particularly well suited for Tunable Diode Laser Spectroscopy due to their intrinsic characteristics. Indeed, the low threshold single frequency emission producing a circular low divergence output beam is beneficial for the development of compact and low power consumption systems for gas spectroscopy. However, in the 3-4 µm range, which encompasses strong absorption bands of many species, only few VCSELs operating either at room temperature (RT) in pulsed mode [1] or in continuous wave (CW) at low temperature [2] have been reported so far. To demonstrate VCSEL operating in the CW regime above RT, we propose a new alternative. This approach is based on Interband Cascade (IC) design for the active region, an arsenide oxide lateral confinement schema, a hybrid-mirror technology and on an intracavity contact (Fig. 1). To provide efficient emission in the 3-4 µm range, the active region is based on a Sb-based IC type-II "W" QW structure. Principal characteristics of Sb-based QW lasers, such as the emission wavelength and threshold, are strongly affected by the growth temperature of the layers located above the active region. We studied a set of edge emitting ICLs designed to operate at 3.3 µm. The lasers were fabricated by Molecular Beam Epitaxy (MBE) on GaSb substrates and their AlGaAsSb top cladding layers were grown at different temperatures. When the growth temperature of the top cladding layer is higher than the optimal one which is used for the active region (435°C), a significant increase of the threshold current densities is observed while the emission wavelength is blue-shifted. This performance degradation is attributed to the inter-diffusion occurring in the active region during the growth. Indeed, it broadens the interfaces and leads to the shift of the quantum level to higher energy, affecting the injection efficiency. Using the optimized growth conditions, we succeeded to fabricate lasers emitting at 3.3 µm and operating in the CW regime up to 80°C (Fig. 2), which confirms the potential of the developed active region. Since the DBRs thickness scales with the wavelength, a fully monolithic approach is not viable in this wavelength range. For this reason, we employed a hybrid VCSEL configuration with a semiconductor AlAsSb/GaSb DBR in the bottom part of the device and a dielectric DBR on the top. Another issue in the VCSEL design is the high electrical resistance of the AlAsSb/GaSb DBR resulting in the overheating of the device. To reduce the ohmic losses we employed an intracavity injection scheme, to avoid highly doped n-type DBRs (in our case ND~5x10 16 cm-3) and thus reach low optical losses in the VCSEL cavity. The top dielectric DBR is composed of Ge and ZnS and benefits from a large refractive index contrast (n~2) and thus from a wide stop-band. The Fig. 3 presents both reflectivity spectra of a 24 pairs n-doped AlAsSb/GaSb grown by MBE and a 5 pairs Ge/ZnS DBRs deposited by magnetron sputtering. The two DBRs are well centered at 3.3 µm. Finally, to ensure an efficient lateral electro-optical confinement, we propose to use an oxide-aperture similarly as short infrared VCSELs [3]. This approach is based on the metamorphic growth and the selective thermal oxidation of an Al(Ga)As heterostructure on top of a GaSb-based half-VCSEL (Fig. 1). This architecture presents several advantages, and in particular the use of the well-controlled Al(Ga)As oxidation process [4]. As already discussed, the growth temperature above the active region affects strongly the performances of the active region. For this reason, we have first determined, with Hall measurement, that n-type GaAs grown at 435°C on undoped GaAs substrate present a better doping efficiency by using Te instead of the usual Si. This is related to the lower activation energy required with Te. Metamorphic GaAs on GaSb growth will be then realized and carefully studied to determine the electrical and optical properties of such layers. We will show our last achievements towards the realization of MIR-VCSELs.

Background. Free fatty acids, also known as nonesterified fatty acids, are proinflammatory molecules that induce insulin resistance in nonpregnant individuals. Nevertheless, the concentration of these molecules has not been systematically addressed in pregnant women. Objective. This meta-analysis is aimed at evaluating the difference in free fatty acid plasma levels between women with gestational diabetes and healthy pregnant controls and their intrinsic and extrinsic determinants. Methods. We performed a systematic search to find relevant studies published in English and Spanish using PubMed, SCOPUS, and ISI Web of Knowledge. We included observational studies measuring the mean plasma levels of free fatty acids among gestational diabetes and healthy pregnant women, with at least ten subjects being analyzed in each group. The standardized mean difference (SMD) by random effects modeling was used. Heterogeneity was assessed using Cochran’s Q, H, and I2 statistics. Results. Among the 290 identified studies, twelve were selected for analysis. A total of 2426 women were included, from which 21% were diagnosed as having gestational diabetes. There were significantly higher levels of free fatty acids among women with gestational diabetes (SMD: 0.86; 0.54-1.18; p<0.001) when compared to healthy pregnant controls and between-study heterogeneity (I2=91%). The metaregression analysis showed that the gestational age at inclusion was the only cofactor influencing the mean levels of free fatty acids, indicating a trend towards lower plasma levels of free fatty acids later in gestation (estimate: -0.074; -0.143 to -0.004; p=0.036). No significant publication bias was found nor a trend towards greater results in small studies. Conclusions. Women with gestational diabetes have higher levels of free fatty acids when compared to healthy pregnant controls. More investigation is needed to assess the potential role of free fatty acids in the prediction of gestational diabetes earlier in pregnancy.

The performance of a Glaucoma assessment system is highly affected by the number of labelled images used during the training stage. However, labelled images are often scarce or costly to obtain. In this paper, we address the problem of synthesising retinal fundus images by training a Variational Autoencoder and an adversarial model on 2357 retinal images. The innovation of this approach is in synthesising retinal images without using previous vessel segmentation from a separate method, which makes this system completely independent. The obtained models are image synthesizers capable of generating any amount of cropped retinal images from a simple normal distribution. Furthermore, more images were used for training than any other work in the literature. Synthetic images were qualitatively evaluated by 10 clinical experts and their consistency were estimated by measuring the proportion of pixels corresponding to the anatomical structures around the optic disc. Moreover, we calculated the mean-squared error between the average 2D-histogram of synthetic and real images, obtaining a small difference of 3e-4. Further analysis of the latent space and cup size of the images was performed by measuring the Cup/Disc ratio of synthetic images using a state-of-the-art method. The results obtained from this analysis and the qualitative and quantitative evaluation demonstrate that the synthesised images are anatomically consistent and the system is a promising step towards a model capable of generating labelled images., We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this research. This work was supported by the Project GALAHAD [H2020-ICT-2016-2017, 732613]

Direct ink writing, a type of additive manufacturing, has been used to fabricate near-net shaped boron carbide (B 4 C) specimens at room temperature with aqueous suspensions. Suspensions with B 4 C solids loading of 48–56 vol.% were dispersed with polyethlenimine (PEI, 25,000 and 750,000 g/mol) and exhibited yield-pseudoplastic behavior. Specimens with filament layer shape retention were produced with suspensions with 50–56 vol.% B 4 C and yield stresses ≥43 Pa and equilibrium storage moduli ≥700 Pa. No residual porosity or cracking between deposited layers was observed in any samples. However, warpage was observed in some green body specimens and was minimized through use of a low molecular weight polymer and reduction of the B 4 C solids loading. Optimal specimens with high filament layer shape retention and no warpage were produced with suspensions containing 54 vol.% B 4 C and 25k g/mol PEI.

Observed sulfur dioxide (SO2) mixing ratios onboard unmanned aerial systems (UAS) during March 11–13, 2013 are used to constrain the three-day averaged SO2 degassing flux from Turrialba volcano within a Bayesian inverse modeling framework. A mesoscale model coupled with Lagrangian stochastic particle backward trajectories is used to quantify the source-receptor relationships at very high spatial resolutions (i.e.

Aqueous suspensions of zirconium diboride (ZrB2), boron carbide (B4C) and tungsten carbide (WC) with dispersant and water-soluble polyvinylpyrrolidone (PVP) were investigated for processing by room-temperature injection molding, a novel, environmentally benign ceramic processing method. B4C and WC were used as sintering aids, and the as-received powders were attrition milled to reduce particle size to promote full densification of ZrB2 specimens by pressureless sintering. Zeta potential measurements of individual ZrB2, B4C and WC powders and of powder mixtures revealed that maximum stability was achieved in aqueous solutions of attrition milled powder mixtures dispersed using an ammonium polyacrylate dispersant. A maximum powder loading of 49 vol% with ≤5 vol% PVP was attained for ZrB2/B4C/WC suspensions with dispersant. Although exhibiting a time-dependent rheological response determined by parallel-plate rheometry, suspensions containing 49 vol% powders and ≤3 vol% PVP, as well as suspensions of 46 vol% powders and ≤4 vol% PVP, were flowable under the conditions of the process. ZrB2 rings prepared by room-temperature injection molding were machinable prior to binder removal and exhibited maximum brown densities of 56% true density (TD). Sintered densities were >98%TD with ~20% linear shrinkage. Scanning electron microscopy revealed an average grain size of 7.3±2.8 µm, and chemical analysis confirmed that no undesirable oxide phases remained in the sintered ZrB2 specimens. Aqueous ZrB2-based suspensions containing B4C and WC sintering aids and PVP were effectively processed via room-temperature injection molding to yield dense ZrB2 rings after binder burnout and pressureless sintering.

The SHADOZ network was assembled to validate a new generation of ozone-monitoring satellites and to better characterize the vertical structure of tropical ozone in the troposphere and stratosphere. Beginning with nine stations in 1998, more than 7000 ozone and P-T-U profiles are available from 14 SHADOZ sites that have operated continuously for at least a decade. We analyze ozone profiles from the recently reprocessed SHADOZ dataset that is based on adjustments for inconsistencies caused by varying ozonesonde instruments and operating techniques. First, sonde-derived total ozone column amounts are compared to the overpasses from the EP/TOMS, OMI and OMPS satellites that cover 1998-2016. Second, characteristics of the stratospheric and tropospheric columns are examined along with ozone structure in the tropical tropopause layer (TTL). We find that: (1) Relative to our earlier evaluations of SHADOZ data, in 2003, 2007 and 2012, sonde-satellite total ozone column offsets at 12 stations are 2% or less, a significant improvement. (2) As in prior studies, the ten tropical SHADOZ stations, defined as within +19 degrees latitude, display statistically uniform stratospheric column ozone, 229 + 3.9 DU, and a tropospheric zonal wave-one pattern with a 14 DU mean amplitude. (3) The TTL ozone column, which is also zonally uniform, masks complex vertical structure; this argues against using satellites for lower stratospheric ozone trends. (4) Reprocessing has led to more uniform stratospheric column amounts across sites and reduced bias in stratospheric profiles. As a consequence the variability in total column ozone now averages 5%.

Technology advances in the field of small, unmanned aerial vehicles and their integration with a variety of sensor packages and instruments, such as miniature mass spectrometers, have enhanced the possibilities and applications of what are now called unmanned aerial systems (UAS). With such technology, in situ and proximal remote sensing measurements of volcanic plumes are now possible without risking the lives of scientists and personnel in charge of close monitoring of volcanic activity. These methods provide unprecedented, and otherwise unobtainable, data very close in space and time to eruptions, to better understand the role of gas volatiles in magma and subsequent eruption products. Small mass spectrometers, together with the world's smallest turbo molecular pump, have being integrated into NASA and University of Costa Rica UAS platforms to be field-tested for in situ volcanic plume analysis, and in support of the calibration and validation of satellite-based remote sensing data. These new UAS-MS systems are combined with existing UAS flight-tested payloads and assets, such as temperature, pressure, relative humidity, SO2, H2S, CO2, GPS sensors, on-board data storage, and telemetry. Such payloads are capable of generating real time 3D concentration maps of the Turrialba volcano active plume in Costa Rica, while remote sensing data are simultaneously collected from the ASTER and OMI space-borne instruments for comparison. The primary goal is to improve the understanding of the chemical and physical properties of emissions for mitigation of local volcanic hazards, for the validation of species detection and abundance of retrievals based on remote sensing, and to validate transport models.

Background The genetic and antigenic characteristics of influenza A viruses (IAV) within and between species change over time due to antigenic shift and drift. Although pigs are known to play a key role in the epidemiology of IAV between species, little is known about the molecular evolution of IAV hemagglutinin (HA) in pigs. Objectives The aim of this study was to evaluate the HA drift of an H1N1 IAV after infecting weaned pigs with or without maternally derived passive immunity. Methods Three- to four-week-old piglets born either to vaccinated or unvaccinated sows were contact-infected upon exposure with an IAV-infected pig. Nasal swabs were collected daily from each pig and tested for IAV by RRT-PCR. Full-length HA sequences were obtained directly from positive nasal swabs and compared between groups. Results Synonymous and non-synonymous mutations were detected in pigs with and without passive immunity. Most of the non-synonymous mutations occurred within the HA1 region of the HA. Changes within HA1 region were only identified in antigenic site B in pigs without passive immunity and in antigenic sites A, B, and D in pigs with passive immunity. However, there was no association between the immune status of the pig and the amino acid substitutions observed. Conclusions Overall, we demonstrated that amino acid substitutions within antigenic sites can happen in weaned pigs with or without passive immunity shortly after infection.

Glaucoma is an asymptomatic eye disease and one of the major causes of irreversible blindness worldwide. For this reason, there have been significant advances in automatic screening tools for early detection. In this paper, an automatic glaucoma diagnosis algorithm based on retinal fundus image is presented. This algorithm uses anatomical characteristics such as the position of the vessels and the cup within the optic nerve. Using several color spaces and the Stochastic Watershed transformation, different characteristics of the optic nerve were analyzed in order to distinguish between a normal and a glaucomatous fundus. The proposed algorithm was evaluated on 53 images (24 normal and 29 glaucomatous images). The specificity and sensitivity obtained by the proposed algorithm are 0.81 and 0.87 using Luv color space, which means considerable performance in diagnosis systems.

A small, 24 V powered, portable mass spectrometer system, named ULISSES, for the study and visualization of gaseous volcanic emission is described. First deployments of the system have focused on both ground and airborne in situ measurement to monitor the awakening of the Turrialba Volcano in Costa Rica. Key gas measurements were acquired prior and after its eruption on 5 January 2010, confirming the presence of gas chemistry precursors typical of volcanic eruptions. Ground and airborne measurements were acquired to gain volcanological insight and as the first step towards the use of unmanned aerial vehicles (UAVs) as future airborne platforms and to confirm its unique capability to serve as a calibration/validation tool for satellite remote sensing data. Low parts per million (ppm) levels of helium and a large concentration of sulfur dioxide were measured in situ after the initial eruption. In particular, the SO2 data correlated with satellite remote sensing data.

Kennedy Space Center (KSC) has developed a portable mass spectrometer (MS) system that is capable of flight from sea level to 44,000 feet (13.4 km), totally autonomous and capable of monitoring permanent gases as well as organics up to 200 Thompson (Th ≡ amu/e). This article presents information about the system.

We present preliminary test results for the integration of a miniature crossed electric and magnetic field mass spectrometer (MS) and a small commercial gas chromatograph (GC). We targeted the experiments to identify design variables for the next generation of field-portable low-cost micro-GC–MS instruments to be developed at Lawrence Livermore National Laboratory for identification of chemical warfare agents (CWAs) and, specifically, to evaluate the potential usage of the commercial version of the compact double-focusing MS (CDFMS) as the detector component.

A miniature double-focusing mass spectrometer with an 8 mm radius was tested at the Advanced Space Propulsion Laboratory (ASPL) at NASA Johnson Space Center (JSC). The purpose of these experiments was to provide residual gas-analysis and single-ion-monitoring capabilities for the vacuum chamber where NASA's new plasma propulsion system, the Variable Specific Impulse Magnetoplasma Rocket (VASIMR), is being developed. The instrument used here was an alpha (α) version of the Integrated Leak Detector System (ILD 50) and represents a smaller version of the original 20 mm-radius Compact Double Focusing Mass Spectrometer prototype (CDFMS) developed at the University of Minnesota. The instrument successfully provided gas-composition information on the vacuum test chamber and several different plasma formulations, provided resolving powers close to the theoretical value of 40 at full width half maximum (FWHM) and demonstrated an operational mass range of 1–50 Da.

The principle behind volcanic gas monitoring is that changes in the rate and the composition of the gaseous emissions are associated with major subsurface movement of magma. There has been increased attention directed towards measurements of volcanic gaseous emissions in order to gain a better comprehension of the precursor signals of eruptive activity. There is also a new appreciation of the hazards that gaseous emissions from volcanic sites pose to their immediate surrounding as well as their effects on the atmosphere and global climate. In-situ mass-spectrometer measurements of volcanic gaseous emissions were conducted at several fumarolic sites using a commercial quadrupole mass spectrometer (QMS-300, from SRS Inc) and demonstrated the usefulness of this analytical technique for real-time continuous volcanic gas monitoring applications. The gas concentrations obtained by the MS were in agreement with the values obtained using gas chromatography (GC) at the Hawaiian Volcano Observatory. In addition, the C/S ratios measured by the MS, using both traditional bottle sampling and in-situ sampling, were found to be very similar. Other gases, such as helium, which it is not possible to monitor with any other continuous technique currently available to volcanologists, were easily detected by the mass spectrometer. The field measurements also provided instrument-performance parameters for an ideal field-deployable mass spectrometer. This is the first of a series of articles aiming at the development of a network of mass spectrometers connected via the Internet for real-time, continuous volcanic gaseous emissions monitoring.

This work is aimed at understanding the aspects of designing a miniature mass spectrometer (MS) system. Several types of small MS systems are evaluated and discussed, including linear quadrupole, quadrupole ion trap, time of flight, and sector. Analysis of hydrogen, helium, oxygen, and argon in a nitrogen background with the concentrations of the components of interest ranging from 0 to 5000 parts per million (ppm). The performance of each system in terms of accuracy, precision, limits of detection, response time, recovery time, scan rate, size, and weight is assessed. The relative accuracies of the systems varied from1% to approximately 40% with an average below 10%. Relative precisions varied from 1% to 20%, with an average below 5%. The detection limits had a large distribution, ranging from 0.2 to 170 ppm. The systems had a diverse response time ranging from 4 to 210 s, as did the recovery time with a 6-to-210-s distribution. Most instruments had scan times near 1 s; however, one instrument exceeded 13 s. System weights varied from 9 to 52 kg and sizes ranged from 15 x 10(3) cm3 to 110 x 10(3) cm3. A performance scale is set up to rank each system, and an overall performance score is given to each system.

The visualization of hazardous gaseous emissions at volcanoes using in-situ mass spectrometry (MS) is a key step towards a better comprehension of the geophysical phenomena surrounding eruptive activity. In-situ data consisting of helium, carbon dioxide, sulfur dioxide, and other gas species, were acquired with a quadrupole based MS system. Global position systems (GPS) and MS data were plotted on ground imagery, topography, and remote sensing data collected by a host of instruments during the second Costa Rica Airborne Research and Technology Applications (CARTA) mission. This combination of gas and imaging data allowed three-dimensional (3D) visualization of the volcanic plume and the mapping of gas concentration at several volcanic structures and urban areas. This combined set of data has demonstrated a better tool to assess hazardous conditions by visualizing and modeling of possible scenarios of volcanic activity. The MS system is used for in-situ measurement of 3D gas concentrations at different volcanic locations with three different transportation platforms: aircraft, auto, and hand-carried. The demonstration for urban contamination mapping is also presented as another possible use for the MS system.