Groundwater recharge sites and pollution sources in the wine-producing Guadalupe Valley (Mexico): Restrictions and mixing prior to transfer of reclaimed water from the US-México border.

Rapid depletion of aquifers in semiarid and arid regions threatens water security. This holds true especially in emerging countries where insufficient knowledge about aquifer systems precludes the implementation of advanced management measures, such as managed aquifer recharge. This study deals with the generation of baseline knowledge for the assessment of aquifers in arid and semiarid regions where artificial recharge with reclaimed water gains increasing impetus. The Guadalupe aquifer in Baja California provides water to 57% of the Mexican wine industry. Recent plans foresee a partial replenishment of its depleted groundwater reserves by transferring treated waste water from the Mexico-USA border for irrigation. The aquifer demonstrated to have a rapid response by rising the water table of about +20 m in relation to natural recharge under an intense rainfall period of 236 mm. Two predominant recharge sources were identified based on a geochemical multi-tracer approach: (a) water of modern age (<5 yr, >1.8 TU) and mixed water of recent-submodern age (3H 0.8-1.8 TU), and (b) sub-modern waters that were recharged before 1952 (3H < 0.5 TU). Water of the first type originate in the main Guadalupe stream, which has a more depleted average δ18O isotope value (-7.8‰) than average local rainwater (-2.0‰). The stream water initially has a Na-HCO3 composition and recharges the entire Calafia zone and most groundwater along the riverbed across the valley. Water of the second type is mostly derived from hill-slope groundwater that has a stable isotope composition of mixed local rainwater and a NaCl composition. High total dissolved solids >2 g l-1 together with enriched NO3- and Se concentrations characterize groundwater in the downstream the Porvenir zone. The geochemical age of this older, hill-slope groundwater suggests that its replenishment takes at least several decades when it becomes exhausted.

Assessing seawater intrusion in an arid coastal aquifer under high anthropogenic influence using major constituents, Sr and B isotopes in groundwater.

The La Paz aquifer system (Baja California Sur, Mexico) is under severe anthropogenic pressure because of high groundwater abstraction for urban supply (city of La Paz, around 222,000 inhabitants) and irrigated agriculture (1900ha). In consequence, seawater has infiltrated the aquifer, forcing the abandonment of wells with increased salinity. The objective of this study was to assess seawater intrusion, understand the hydrogeochemical processes involved and estimate the contribution of seawater in the wells tested. The aquifer comprises mainly the alluvial filling and marine sediments of a tectonic graben oriented north-south, in contact with the Gulf of California. Groundwater samples were collected in 47 locations and analyzed for major constituents. A subset of 23 samples was analyzed for strontium and boron concentrations and isotopic signatures (87Sr/86Sr and δ11B). Results were interpreted using standard hydrochemical plots along with ad hoc plots including isotopic data. Seawater intrusion was confirmed by several hydrogeochemical indicators, such as the high salinity in areas of intense pumping or the Na+-Ca2+ exchange occurring in sediments that were previously in chemical equilibrium with fresh water. However, seawater contribution was not sufficient to explain the observed concentrations and isotopic signatures of Sr and B. According to the isotopic data, desorption processes triggered by a modification in chemical equilibrium and an increase in ionic strength by seawater intrusion significantly increased Sr and probably B concentrations in groundwater. From a calculation of seawater contribution to the wells, it was estimated that one-third of the sampled abstraction wells were significantly affected by seawater intrusion, reaching concentrations that would limit their use for human supply or even irrigated agriculture. In addition, significant agricultural pollution (nitrates) was detected. Planned management of the aquifer and corrective measures are needed in order to invert the salinization process before it severely affects water resources in the long term.

Comparison of Two Electromagnetic Navigation Systems For CT-Guided Punctures: A Phantom Study.

PURPOSE: We compared the targeting accuracy and reliability of two different electromagnetic navigation systems for manually guided punctures in a phantom. MATERIALS AND METHODS: CT data sets of a gelatin filled plexiglass phantom were acquired with 1, 3, and 5 mm slice thickness. After paired-point registration of the phantom, a total of 480 navigated stereotactic needle insertions were performed manually using electromagnetic guidance with two different navigation systems (Medtronic Stealth Station: AxiEM; Philips: PercuNav). A control CT was obtained to measure the target positioning error between the planned and actual needle trajectory. RESULTS: Using the Philips PercuNav, the accomplished Euclidean distances were 4.42 ±â€Š1.33 mm, 4.26 ±â€Š1.32 mm, and 4.46 ±â€Š1.56 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.84 ±â€Š1.59 mm, 3.84 ±â€Š1.43 mm, and 3.81 ±â€Š1.71 mm, respectively. Using the Medtronic Stealth Station AxiEM, the Euclidean distances were 3.86 ±â€Š2.28 mm, 3.74 ±â€Š2.1 mm, and 4.81 ±â€Š2.07 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.29 ±â€Š1.52 mm, 3.16 ±â€Š1.52 mm, and 3.93 ±â€Š1.68 mm, respectively. CONCLUSION: Both electromagnetic navigation devices showed excellent results regarding puncture accuracy in a phantom model. The Medtronic Stealth Station AxiEM provided more accurate results in comparison to the Philips PercuNav for CT with 3 mm slice thickness. One potential benefit of electromagnetic navigation devices is the absence of visual contact between the instrument and the sensor system. Due to possible interference with metal objects, incorrect position sensing may occur. In contrast to the phantom study, patient movement including respiration has to be compensated for in the clinical setting. KEY POINTS: • Commercially available electromagnetic navigation systems have the potential to improve the therapeutic range for CT guided percutaneous procedures by comparing the needle placement accuracy on the basis of planning CT data sets with different slice thickness. Citation Format: • Putzer D, Arco D, Schamberger B et al. Comparison of Two Electromagnetic Navigation Systems For CT-Guided Punctures: A Phantom Study. Fortschr Röntgenstr 2016; 188: 470 - 478.

Biotransformation of Endocrine-Disrupting Compounds in Groundwater: Bisphenol A, Nonylphenol, Ethynylestradiol and Triclosan by a Laccase Cocktail from Pycnoporus sanguineus CS43.

The biodegradation of organic compounds present in water at trace concentration has become a critical environmental problem. In particular, enzymatic oxidation by fungal laccases offers a promising alternative for efficient and sustainable removal of organic pollutants in water. In this work, the biocatalytic ability of laccases from the Pycnoporus sanguineus CS43 fungus was evaluated. A filtered culture supernatant (laccase cocktail) evidenced an enhanced biotransformation capability to remove common endocrine-disruptor compounds (EDCs), such as bisphenol A, 4-nonylphenol, 17-α-ethynylestradiol and triclosan. A biodegradation of around 89-100 % was achieved for all EDCs using synthetic samples (10 mg L-1) and after the enzymatic treatment with 100 U L-1 (50.3 U mg -1). The biodegradation rates obtained were fitted to a first order reaction. Furthermore, enzymatic biocatalytic activity was also evaluated in groundwater samples coming from northwestern Mexico, reaching biotransformation percentages between 55 and 93 % for all tested compounds. As far as we know this is the first study on real groundwater samples in which the enzymatic degradation of target EDCs by a laccase cocktail from any strain of Pycnoporus sanguineus was evaluated. In comparison with purified laccases, the use of cocktail offers operational advantages since additional purification steps can be avoided.

[The prevalence of postural disorders in children and adolescents: a cross sectional study]. / Die Prävalenz von Haltungsstörungen bei Kindern und Jugendlichen: eine Querschnittsanalyse.

AIM: Postural insufficiency in children and adolescents is considered as a risk factor for back pain. The evaluation is performed through the Matthiass arm-raising test, a visual test procedure with a high risk of subjective interpretation. Therefore, the prevalence data for postural insufficiency differ over a wide range in the literature. This study is focuses on the prevalence of postural insufficiency before and during adolescence with an objective test procedure and a more accurate interpretation of the Matthiass arm-raising test. METHOD: Pictures of 663 children, examined through the photographically documented Matthiass arm-raising test, were measured with specially developed software on the monitor. The degree of body trunk inclination indicating the postural stability power allows one to accurately define the following categories: postural stability, postural impairment and postural decline. RESULTS: 34% of children at the age of 8 to 9 years show a postural insufficiency which is evenly distributed between postural impairment and postural decline for both genders. At the age of 11 to 14 years, postural insufficiency decreases to 19%. The decline, especially for severe forms, is predominant in boys. CONCLUSION: Before the adolescence period, postural insufficiency is distributed evenly with regard to both form and gender, while a noticeable decline shows up as the age increases. The decline for girls seems to be less caused by the earlier entry into adolescence.

[The KIL-system for qualitative and quantitative evaluation of posture in lateral view]. / Das KIL-Schema zur qualitativen und quantitativen Beurteilung der Körperhaltung im seitlichen Profil.

AIM: To register also minor variations of posture sa simple and economic procedure should be worked out to categorize posture types concerning quality as well quantity. METHOD: On the Image of the lateral body profile three reference points were determined which allow us to measure two distances and two angles. RESULTS: The relation of the two distances reflects the degree of kyphosis, the angles indicate on the one hand the inclination of the spinal sagittal configuration and on the other hand the degree of lordosis. The measured values are shown in the Kyphosis-Inclination-Lordosis system (KIL system). The components of measurement have proved successful also for static as well as for dynamic posture assessments. The method was simple and economic as postulated. CONCLUSION: The method allowed us to analyse reliably the effect of active primary Intervention also for minor variations in posture on pupils at the age of 11 to 15 over a period of three years. The quantitative analyse made it possible - contrarily to the usual postural types going by what Staffel said - to define subcategories and with it a precise selection of individuals who need a secondary intervention. The method has been set up for check-ups in school, but an application to other groups should be possible.