714 research outputs found

    Prevention of Acute Hematoma After Face-Lifts

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    Acute hematoma remains one of the most frequently encountered complications after face-lift surgery. Several risk factors inherent to the patient and omission of certain intraoperative regimens are considered to cause hematoma. Significant risk factors include high blood pressure and male gender. Possible intraoperative regimens for the prevention of hematoma include tumescence infiltration without adrenaline, clotting of raw surfaces with fibrin glue, usage of drains, and application of compression bandages. However, little attention has been paid to postoperative measures. To examine whether different regimens in the postoperative phase can influence the incidence of hematoma, all face-lift patients who underwent surgery by a single surgeon in two different clinics (n=376) with two different postoperative regimens were evaluated over the course of 3years. In group 1 (n=308), all postoperative medication was administered on request including medication for pain control, blood pressure stabilization, and prevention of nausea and vomiting as well as postoperative restlessness and agitation. In group 2 (n=68), this medication was administered prophylactically at the end of the operation before extubation. The hematoma rate was 7% in group 1 and 0% in group 2. This study showed that the prophylactic use of medications (e.g., analgesics, antihypertonics, antiemetics, and sedatives) during the postoperative phase is superior to making drugs available to patients on request and can decrease the occurrence of acute hematoma in face-lift patient

    Technical Note: Field experiences using UV/VIS sensors for high-resolution monitoring of nitrate in groundwater

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    peer-reviewedTwo different in situ spectrophotometers are compared that were used in the field to determine nitrate-nitrogen (NO3-N) concentrations at two distinct spring discharge sites. One sensor was a double wavelength spectrophotometer (DWS) and the other a multiple wavelength spectrophotometer (MWS). The objective of the study was to review the hardware options, determine ease of calibration, accuracy, influence of additional substances and to assess positive and negative aspects of the two sensors as well as troubleshooting and trade-offs. Both sensors are sufficient to monitor highly time-resolved NO3-N concentrations in emergent groundwater. However, the chosen path length of the sensors had a significant influence on the sensitivity and the range of detectable NO3-N. The accuracy of the calculated NO3-N concentrations of the sensors can be affected if the content of additional substances such as turbidity, organic matter, nitrite or hydrogen carbonate significantly varies after the sensors have been calibrated to a particular water matrix. The MWS offers more possibilities for calibration and error detection but requires more expertise compared with the DWS.The authors would like to acknowledge the Teagasc Walsh Fellowship scheme for funding the study in Ireland, and the German federal Ministry of Education and Research (BMBF) for sponsoring the SMART-project (grant no. 02WM1079-1086, 02WM1211-1212) for the study in Jordan.Teagasc Walsh Fellowship Programm

    Development and structure of karstification of the Dong Van Karst Plateau UNESCO Global Geopark, North Vietnam based on cave survey data

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    This paper presents a quantitative study of the relationship between the cave system and the tectonic and karst evolution of the Dong Van Karst Plateau based on analysis and statistics of geometric parameters and orientation of cave passages. The region is located in northern Vietnam and belongs to the extended part of the South China karst belt (Yunnan karst plateau), which is composed mainly of carbonate rocks. Cave classification based on cave conduits geometric parameters shows that caves developed mainly in the vadose zone (27 vadose branchwork caves, 10 mixed caves developed under the control of fault systems, and 12 water-table caves). The degree of correlation between cave levels and planation surfaces suggests that the development of horizontal cave passages is related to two levels of planation surfaces, including one at 1250–1450 masl (equivalent to cave level at 1350–1450 masl), and at 1000–1250 masl (corresponding to cave level at 1200–1250 masl). Additionally, cave passage orientation shows that the cave system formed and developed under the influence of tectonic activities in the Cenozoic. The dominant orientation trend is roughly in the East–West direction and occurred in the early phase (Eocene–Miocene). Next is a trend roughly North–South that occurred in the late phase (Pliocene–Quaternary). The last orientation trend follows the NW–SE direction due to the reactivation of paleo-fault systems in the same direction. Although there are limitations due to accessibility and the level of cave exploration, this research suggests that analysis and statistics of the geometric parameters and orientation of cave passages based on cave survey data can be one of the effective approaches used to identify the development and structure of karstification in the karst region

    Timing preferences for women's family life transitions: Intergenerational transmission among migrants and Dutch

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    This study examines the transmission of preferences regarding the timing of family-life transitions of women among migrant and native Dutch families. We study how and to what extent parental preferences, migrant origin, and family characteristics affect the child’s timing preferences. We use parent and child data (N ¼ 1,290) from the Netherlands Kinship Panel Study (2002, 2003) and the Social Position and Provisions Ethnic Minorities Survey (2002). Regression analyses reveal that parental timing preferences regarding family-life transitions are strongly associated with the timing preferences of their children. Analyses also show that these preferences strongly vary by migrant origin, educational level, and religious involvement.The process of intergenerational transmission, however, is found to be very similar among migrants and Dutch

    Gender differences in the impact of family background on leaving the parental home

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    We address the question to what extent characteristics of the family of origin influence the timing of leaving the parental home and to what extent these effects differ between men and women. We use data from the Netherlands Kinship Panel Study to examine the effects of parental resources, atmosphere in the family of origin and family structure on leaving home to live without a partner and leaving home to live with a partner. The results indicate that a pleasant atmosphere in the parental home decreases the risk of leaving home and living in stepfamilies or single-parent families increases this risk. The availability of parental resources leads to a decreased risk of leaving home at young ages, but an increased risk at later ages. Many of these effects are found for both men and women and for both pathways out of the home. Furthermore, we find evidence that women are affected more strongly by family background characteristics than men are

    Ecohydrogeology: The interdisciplinary convergence needed to improve the study and stewardship of springs and other groundwater-dependent habitats, biota, and ecosystems

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    This essay discusses the need for, advantages and challenges of integrating the scientific disciplines of ecology and hydrogeology in the study of groundwater-dependent ecosystems (GDEs). We provide a definition for ecohydrogeology as \u201ca unifying, synthetic field of study integrating the approaches from the ecological and hydrogeological sciences in the study of groundwater (GW)-related ecosystems, habitats, and organisms to advance science, stewardship, and policy\u201d. We selected specific case studies to illustrate first how hydrogeological approaches can favour in-depth understanding and modelling of springs and crenobiontic (spring-dependent) species distribution, assemblage composition and organization. Second, this essay also examines how taxa and assemblages serve as bioassays and ecosystem indicators to infer hydrogeological aspects of GW flow and discharge, as well as quantitative and qualitative human impacts. We consider both types of features and parameters as ecohydrogeological indicators. The examples presented include topics related to springs and other GDE geomorphological types and classification, GW quality influences on crenobiont distribution, phreatophyte (= plant species the roots of which reach to and into the water table) ecophysiology in relation to water table depth, and flow variability in karstic systems, to nutrient dynamics in relation to dinoflagellate blooms in GDE montane lakes. Conceptual approaches that integrate ecology with hydrogeology include the investigation of GDE distribution and ecology, groundwater-surface water (GW-SW) interactions, and the development of the discipline of ecohydrology. Despite widespread applications, the scientific community still lacks a complete or effective integration of the principles described in the fields of groundwater hydrogeology with ecology, ecophysiology, and environmental biology. Springs are aquatic-wetland-riparian habitats that link shallow subsurface-surface processes and assemblages, often functioning as biodiversity hotspots, ecotones, keystone, and refugial ecosystems, for which coordination between studies of hydrogeology and ecology are both obvious and essential. Over the past century, springs ecosystem ecology has been largely ignored by hydrologists, and, conversely, hydrogeology has been under-emphasized by ecologists. Recent global recognition of the extraordinary biodiversity and socio-cultural significance of springs, coupled with their globally highly threatened conservation status, stimulated this inquiry into how to better integrate hydrogeology with springs ecosystem ecology. Acknowledging the highly threatened status of springs ecosystems around the world, there is an urgent need to integrate and invigorate the union of these disciplines into ecohydrogeology, the study of groundwater-dependent organisms, habitats, ecosystems, and management policy

    Dynamics of water fluxes and storages in an Alpine karst catchment under current and potential future climate conditions

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    Karst aquifers are difficult to manage due to their unique hydrogeological characteristics. Future climate projections suggest a strong change in temperature and precipitation regimes in European karst regions over the next decades. Alpine karst systems can be especially vulnerable under changing hydro-meteorological conditions since snowmelt in mountainous environments is an important controlling process for aquifer recharge and is highly sensitive to varying climatic conditions. Our paper presents the first study to investigate potential impacts of climate change on mountainous karst systems by using a combined lumped and distributed modeling approach with consideration of subsurface karst drainage structures. The study site is characterized by high-permeability (karstified) limestone formations and low-permeability (non-karst) sedimentary Flysch. The model simulation under current conditions demonstrates that a large proportion of precipitation infiltrates into the karst aquifer as autogenic recharge. Moreover, the result shows that surface snow storage is dominant from November to April, while subsurface water storage in the karst aquifer dominates from May to October. The climate scenario runs demonstrate that varied climate conditions significantly affect the spatiotemporal distribution of water fluxes and storages: (1) the total catchment discharge decreases under all evaluated future climate conditions. (2) The spatiotemporal discharge pattern is strongly controlled by temperature variations, which can shift the seasonal snowmelt pattern, with snow storage in the cold season (December to April) decreasing significantly under all change scenarios. (3) Increased karst aquifer recharge in winter and spring, and decreased recharge in summer and autumn, partly offset each other. (4) Impacts on the karst springs are distinct; the lowest permanent spring presents a robust discharge behavior, while the highest overflow outlet is highly sensitive to changing climate. This analysis effectively demonstrates that the impacts on subsurface flow dynamics are regulated by the characteristic dual flow and spatially heterogeneous distributed drainage structure of the karst aquifer. Overall, our study highlights the fast groundwater dynamics in mountainous karst catchments, which make them highly vulnerable to future changing climate conditions. Additionally, this work presents a novel holistic modeling approach, which can be transferred to similar karst systems for studying the impact of climate change on local karst water resources with consideration of their individual hydrogeological complexity and hydraulic heterogeneity.</p

    Tracking flowpaths in a complex karst system through tracer test and hydrogeochemical monitoring: Implications for groundwater protection (Gran Sasso, Italy)

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    Groundwater in karst aquifers is frequently tapped for drinking purposes, due to frequent huge volumes of resources. Unfortunately, vulnerability of these aquifers can be high, due to possible fast transfer of recharge water on springs by the karst network. On Gran Sasso Mountain regional aquifer, several springs are subjected to drinking withdrawal and an updated evaluation of their potential is now a fundamental issue to be considered, facing climate change effects, which reflect on variation of discharge regimen and values. To distinguish between different contribution of spring recharge, a tracer test has been carried out on the Vitella d’Oro spring, fed both by the regional aquifer and by a local system exposed to karst features developed in the Rigopiano Conglomerates formation. Thanks to hydrogeological, hydrogeochemical and isotopic data, a conceptual model of spring recharge has been proposed and subsequently validated by the tracer test results. All information confirms the superimposition on the regional base flow, by a relevant contribution of the karst network, influencing the spring discharge in recharge periods. In detail, a fast flow component is responsible for discharge peaks and frequently of turbidity events, having a mean velocity ranging from 30 to 70 m/h in the aquifer. Besides of this fast flow, an additional aliquot of the recharge is due to the same local aquifer, but slower flow clearly identifiable by hydrochemistry and isotopic data. Thanks to these findings, a renewed manage- ment of the spring has been suggested, considering the different degrees of aquifer vulnerability (turbidity occurrence) directly related to the discharge regimen

    Carbonate rocks and karst water resources in the Mediterranean region

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    Carbonate rocks in the Mediterranean region form karst landscapes with a variety of morphological and hydrological features, and are of particular interest from a water management perspective as they represent major karst aquifers. The Mediterranean Karst Aquifer Map and Database (MEDKAM) provides a 1:5,000,000 scale map showing the distribution of carbonate and evaporite rocks that can host karst groundwater resources, with additional information on other hydrogeological settings, selected terrestrial and submarine karst springs, caves and karst groundwater-dependent ecosystems. A statistical evaluation shows that carbonate rocks cover ~39.5% of the Mediterranean region within a 250-km focus area from the coastline. North Africa has the largest continuous area of carbonate rocks, while smaller countries in the Middle East and the Dinarides have the largest proportion of carbonate rocks in relation to their total area. Carbonate rocks are also widespread in coastal areas, occurring along ~33.6% (14,000&nbsp;km) of the total Mediterranean coastline, including large islands such as Crete and Mallorca, and ~25.9% (6,400&nbsp;km) of the continental coastline. Two additional maps display (1) groundwater recharge, showing a climatic gradient from north to south, and (2) groundwater storage trends, indicating a mean annual karst groundwater loss from 2003 to 2020 of 436 million m3 in the 250-km area. This study quantifies the carbonate rocks in the Mediterranean region and shows their importance for groundwater resources. MEDKAM will serve as a basis for further research and improved international cooperation in karst groundwater management

    Urgent plea for global protection of springs

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    Springs, keystone ecosystems, are rapidly disappearing mainly due to overexploitation, and need global protection
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