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1.
We report a neonatal case of systemic pseudohypoaldosteronism type 1 caused by a novel mutation in the SCNN1A gene (homozygous c.1052 + 2dupT in intron 3) in which the patient presented with life-threatening hyperkalemia, hyponatremia and metabolic acidosis. It remains uncertain if there is genotype–phenotype correlation, due to the rarity of the disease. This mutation, which to our best knowledge has not been described before, was associated with a very severe phenotype requiring aggressive therapy.  相似文献   

2.
Macao is a population-dense society that depends heavily on exogenous natural resources. In parallel with an expanding gambling sector, tourism became the most important driving force in Macao's economy. Economic growth in Macao has now benefited from the gambling boom and associated tourism for more than two decades. Although traditional economic theory has been used to deal with the economics of the gambling sector, the materials and energy foundation for this sector has not been previously analyzed. This is an important omission from the literature, since the gambling sector provides gamblers with food, tickets, services, water, electricity, equipment, labor, and other services that consume large quantities of materials and energy. In this paper, emergy synthesis is introduced to analyze Macao's gambling sector in 2004. Macao's casinos provide a dense flow of services that favor gambling tourists, since the emergy/$ ratio (1.42 × 1012 sej/$) for the sector is much lower than that for Macao as a whole (2.38 × 1012 sej/$). The emergy imports by this sector totaled 78.1 × 1020 sej, and its exports were 77.1 × 1020 sej. The emergy of services therefore plays an important role in Macao's gambling sector, and the transformity of an employee in this sector (11.2 × 1016 sej/person) was much higher than that of a typical person in Macao (5.27 × 1016 sej/person).  相似文献   

3.
《Ecological Indicators》2007,7(2):489-496
Biomonitoring of mercury pollution of Dubasari reservoir of the Dniester River has been carried out using macrophytes, epiphytosuspensions and lichens. Macrophytes uptake mercury from water column and bottom sediments in the succession Potamogeton pectinatus L. > Myriophyllum verticillatum L. > Potamogeton perfoliatus L. > Butomus umbellatus L. These species possess the properties of bio-indicators. The mercury content in their biomass is in good positive correlation (r = 0.908–0.990) with the mercury content both in water and bottom sediments. It has been shown that the maximum mercury content in these bio-indicators is found in the area of the Rezina–Rybnitsa industrial complex that consists of two cement plants and a metallurgical one. The use of lichens as bio-indicators for the ecological state of the air in the vicinity of the investigated aquatic ecosystem and of the epiphytosuspensions precipitated on submerged macrophytes, denote the active state of the source for mercury pollution of the Dubasari reservoir.  相似文献   

4.
Buffer zones along rivers and streams can provide water quality services by filtering nutrients, sediment and other contaminants from the surface. Redundancy analysis was used to determine the influence of the landscape pattern at the entire catchment scale and at multiple buffer zone scales (100 m, 300 m, 500 m, 1000 m and 1500 m) on the water quality in a highly urbanised watershed. Change-point analysis was further applied to estimate the specific locations along a gradient of landscape metric that result in a sudden change in the water quality variable. The landscape characteristics for 100 m buffer zones appeared to have a slightly greater influence on the water quality than the entire catchment. The patch density of urban land and the large patch index of water were recognised as the dominant variables influencing the water quality for a 100 m buffer zone. The result of change-point analysis indicated key interval values of the two landscape metrics within the 100 m buffer zone. When the patch density of urban land was >30–40 n/100 ha and the largest patch index of water was >2.5–3.5%, the watershed water quality appeared to be better protected.  相似文献   

5.
Knowledge of the carbon footprint (CF) of a scientific publication can help to guide changes in behavior for mitigating global warming. A knowledge gap, however, still exists in academic circles. We quantified the CF of a publication by parameterizing searches, downloads, reading, and writing in the processes of publication with both direct and indirect emissions covered. We proposed a time-loaded conversion coefficient to transfer indirect emissions to final consumers. A questionnaire survey, certification database of Energy Star, fixed-asset databases specific to our campus, and reviewed life-cycle-assessment studies on both print media and electronic products were integrated with Monte Carlo simulations to quantify uncertainties. The average CF [(CI: 95%), SD] of a scientific publication was 5.44 kg CO2-equiv. [(1.65, 14.78), 4.97], with 37.65 MJ [(0.00, 71.32), 30.40] of energy consumed. Reading the literature contributed the most, followed by writing and searching. A sensitivity analysis indicated that reading efficiency, the proportion of e-reading, and reference quantity were the most dominant of 52 parameters. Durable media generated a higher CF (4.24 kg CO2-equiv.) than consumable media (1.35 kg CO2-equiv.) due to both direct and indirect reasons. Campus policy makers should thus not promote the substitution of e-reading for print reading at the present stage, because their environmental advantages are highly dependent on time-loaded and behavioral factors. By comparison, replacing desktops with laptops is more attractive, by potentially reducing CFs by 50% and the disproportionate consumption of energy.  相似文献   

6.
Preeclampsia is a serious medical complication during pregnancy. In response to an increasing number of preeclamptic cases and scarcity of data concerning the interrelation between trace element levels and preeclampsia, we carried out a hospital based case–control study in Riyadh, Saudi Arabia to study the correlation between levels of serum trace elements and risk of preeclampsia. One hundred and twenty pregnant women were enrolled in this study and divided into three groups of 40 each—Control group, HR group (women at high risk of preeclampsia) and PET group (Preeclampsia group). Serum trace element levels were estimated by inductively coupled plasma optical emission spectrophotometer. The analysis found that mean values of Ca, Mg and Zn were 90.08 ± 6.38, 19.33 ± 3.32 and 1.30 ± 0.83 mg/L respectively in normotensive control and 77.85 ± 4.47, 15.44 ± 1.43 and 0.98 ± 0.63 mg/L respectively in the HR group. The mean values of Ca, Mg and Zn in the preeclamptic group were 70.37 ± 4.66, 13.58 ± 1.98 and 0.67 ± 0.59 mg/L, respectively. Interelement analysis reflected a negative correlation between Ca and Mg and between Mg and Zn whereas positive correlation between Ca and Zn in preeclamptic women. However the correlation was not statistically significant. In conclusion, our study suggests that decreased levels of these trace elements in serum may act as predisposing factors in pathogenesis of Preeclampsia.  相似文献   

7.
Soft tissue artefacts (STA) introduce errors in joint kinematics when using cutaneous markers, especially on the scapula. Both segmental optimisation and multibody kinematics optimisation (MKO) algorithms have been developed to improve kinematics estimates. MKO based on a chain model with joint constraints avoids apparent joint dislocation but is sensitive to the biofidelity of chosen joint constraints. Since no recommendation exists for the scapula, our objective was to determine the best models to accurately estimate its kinematics. One participant was equipped with skin markers and with an intracortical pin screwed in the scapula. Segmental optimisation and MKO for 24-chain models (including four variations of the scapulothoracic joint) were compared against the pin-derived kinematics using root mean square error (RMSE) on Cardan angles. Segmental optimisation led to an accurate scapula kinematics (1.1°  RMSE  3.3°) even for high arm elevation angles. When MKO was applied, no clinically significant difference was found between the different scapulothoracic models (0.9°  RMSE  4.1°) except when a free scapulothoracic joint was modelled (1.9°  RMSE  9.6°). To conclude, using MKO as a STA correction method was not more accurate than segmental optimisation for estimating scapula kinematics.  相似文献   

8.
QuestionsDoes the plant species composition of Thandiani sub Forests Division (TsFD) correlate with edaphic, topographic and climatic variables? Is it possible to identify different plant communities in relation to environmental gradients with special emphasis on indicator species? Can this approach to vegetation classification support conservation planning?LocationThandiani sub Forests Division, Western Himalayas.MethodsQuantitative and qualitative characteristics of species along with environmental variables were measured using a randomly stratified design to identify the major plant communities and indicator species of the Thandiani sub Forests Division. Species composition was recorded in 10 × 2.5 × 2 and 0.5 × 0.5 m square plots for trees, shrubs and herbs, respectively. GPS, edaphic and topographic data were also recorded for each sample plot. A total of 1500 quadrats were established in 50 sampling stations along eight altitudinal transects encompassing eastern, western, northern and southern aspects (slopes). The altitudinal range of the study area was 1290 m to 2626 m above sea level using. The relationships between species composition and environmental variables were analyzed using Two Way Cluster Analysis (TWCA) and Indicator Species Analysis (ISA) via PCORD version 5.ResultsA total of 252 plant species belonging to 97 families were identified. TWCA and ISA recognized five plant communities. ISA additionally revealed that mountain slope aspect, soil pH and soil electrical conductivity were the strongest environmental factors (p  0.05) determining plant community composition and indicator species in each habitat. The results also show the strength of the environment-species relationship using Monte Carlo procedures.ConclusionsAn analysis of vegetation along an environmental gradient in the Thandiani sub Forests Division using the Braun-Blanquet approach confirmed by robust tools of multivariate statistics identified indicators of each sort of microclimatic zones/vegetation communities which could further be used in conservation planning and management not only in the area studied but in the adjacent regions exhibit similar sort of environmental conditions.  相似文献   

9.
10.
Although salivary testosterone (T) is often used in clinical studies accuracy is mostly questionable. State of the art data for men is sparse and for women absent. Our objective was to perform a critical evaluation of salivary T (Sal-T) as a method for indirect assessment of serum T using state of the art methods. Saliva was collected via ‘Salivette’ and ‘passive drooling’ methods. Sal-T and free T in serum after equilibrium dialysis were measured by LC-MS/MSResultsEvaluation of Sal-T results versus free T by equilibrium dialysis (ED-T) for men gave: ‘Salivette’ Sal-T = 0.05 + 0.88x ED-T, r = 0.43; ‘passive drooling’ Sal-T = 0.17 + 0.91x ED-T r = 0.71. In women, correlation was comparable but values are higher than free T: ‘passive drooling’ Sal-T = 0.12 + 2.32x ED-T, r = 0.70. The higher than expected T values in saliva, appear to be explained by T binding to salivary proteins. Iso-electric focusing of saliva proteins, followed by fractionation and LC–MS/MS assay of T showed marked testosterone peaks at pH 5.3 and 8.4, providing evidence for T binding in saliva to proteins such as albumin and proline rich protein (PRP).ConclusionsPassive drooling is the collection method of choice for testosterone in saliva. Sal-T is not directly comparable to serum free T due to T binding to saliva proteins, which substantially affects the low Sal-T in women but not the higher Sal-T in healthy adult men.  相似文献   

11.
Isoxanthopterin (IX) has two edges with hydrogen bond-forming sites suitable for binding to thymine (T) and cytosine (C). The binding affinity of IX for T or C is stronger than for adenine (A) and guanine (G), whereas the base selectivity of IX for T over C (and vice versa) is moderate. In order to improve both the binding affinity and base selectivity for T over C or C over T, a methyl group is introduced respectively at the N-3 or N-8 position of IX. This leads to the known ligands 3-methyl isoxanthopterin (3-MIX) and 8-methyl isoxanthopterin (8-MIX), and the binding affinity for C or T is expected to be tuned and improved by methyl substitution. Indeed, 3-MIX selectively binds to T more strongly than IX with a binding constant of 1.5 × 106 M?1 and it loses its binding affinity for C. In contrast, 8-MIX selectively binds to C over T with a binding constant of 1.0 × 106 M?1 and the binding affinity is greatly improved compared to the parent ligand IX. The thermodynamics of the ligand–nucleotide interaction is analyzed by isothermal calorimetric titrations, and the results show that the interaction follows a 1:1 stoichiometry and is enthalpy-driven. The introduction of methyl groups at both N-3 and N-8 positions results in an increase in enthalpy of the ligand–nucleotide interaction, which leads to the improved binding affinity.  相似文献   

12.
A new diantheramide, 4,4′-dihydroxy-2′-methoxydianthramide (1), and a new cyclic peptide, named segelin I (2) were isolated from the seeds of Vaccaria hispanica. Their structures were elucidated by detailed spectroscopic analysis and chemical methods. Compounds 1 and 2 were revealed to show significantly in vitro α-glucosidase inhibitory activity with IC50 values of 0.080 ± 0.002 mM and 0.28 ± 0.002 mM, respectively, which were more potent than the reference compound acarbose (IC50 0.410 ± 0.001 mM).  相似文献   

13.
The present contribution encompasses the first case study on the aquatic macroinvertebrates as bioindicators for assessing the health of Asan wetland (area 3.2 km2), located in the foothills of Central Himalayas, India. Monthly sampling from all the sampling sites in five replicates was made for a period of 12 months (July 2002–June 2003) at 9:00–11:00 h. A total of 32 species of macroinvertebrates were found with the Ephemeroptera and Gastropoda being the most abundant component of invertebrates communities. The Shannon–Wiener diversity index calculated for macroinvertebrates ranged from 3.50 to 4.61. Seasonal fluctuations in the density of macroinvertebrates revealed maximum density (451–503 ind m?2) during winter and minimum (126–143 ind m?2) during monsoon season. The density of macroinvertebrates was influenced by the anthropogenic disturbances and water level fluctuations causing disturbance in the littoral zone of the wetland. The statistical relationships between turbidity, transparency, dissolved oxygen and water temperature and macroinvertebrates of Asan wetland were also computed for assessing the impact of anthropogenic disturbances on macroinvertebrates.  相似文献   

14.
Islands, which provide multiple ecosystem services, are subject to increasing urbanization pressure due to the ongoing marine development, especially in developing countries. Insights into the island urbanization mechanism and its ecological consequences are essential to sustainable development. In the present paper, the satellite images, nighttime lights, and topographic data were integrated to characterize the spatially explicit urbanization process and mechanism during 1995–2011 in the Zhoushan Island, East China. Furthermore, the corresponding spatially explicit changes in ecosystem services, including net primary productivity (NPP), carbon sequestration and oxygen production (CSOP), nutrient cycling, crop production, and habitat quality, were quantified based on the Carnegie–Ames–Stanford Approach (CASA) and Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) models. The results showed that the Zhoushan Island had experienced a rapid urbanization over the years, with significant urban encroachment on the farmland and tidal flat. Moreover, the urban land expansion was positively correlated with that of the nighttime lights and negatively correlated with the elevation, slope, and the distance to shoreline. These indicated that the urban expansion was resulted from the enhancement of socioeconomic activities, and concentrated in the near-shore areas with low altitude and gentle slope. The urban encroachment on other land use types resulted in a decrease of 3.4 Gg C a−1 NPP, 8.7 Gg a−1 CSOP, 13.2 Gg a−1 nutrient cycling, and 12.3 t a−1 crop production, respectively. In addition, the habitat quality in 11% area of this island degraded substantially. Therefore, to achieve sustainable development of islands, it is urgent to implement more stringent policies, such as island spatial regulation, environmental impact assessment, intensive land use, and urban greening, etc.  相似文献   

15.
The anaerobic digestion technology is a biological treatment widely used to reduce the pollution load of wet waste biomass. In this work we present the results obtained by performing extensive experiments of anaerobic digestion of slaughterhouse waste, tomato industry waste and olive oil industry waste in continuous mode, which were designed to demonstrate that anaerobic digestion is an effective technology from an environmental and economic point of view.Biogas yields obtained are between 35.22 and 5.45 Nm3 biogas/m3 olive oil industry waste and tomato industry waste respectively and the slaughterhouse wastes achieve intermediate production, 30.86 Nm3 biogas/m3 municipal slaughterhouse waste and 22.53 Nm3 biogas/m3 Iberian pig slaughterhouse waste. Moreover, it possible to degrade between 63.46 and 75.3% of the initial organic matter.If these results are analyzed, the environmental, energetic economic benefits of anaerobic digestion can be quantified. Biomethanation of all these wastes generated annually in Extremadura could prevent the emission of 134,772 t of equivalent carbon dioxide, generate an energy similar to that provided by 2826 toe and reach payback times from 3.29 to 3.75 years for anaerobic digestion plant designed to treat the wastes generated by a medium-sized industry. So, we have fulfilled all the planned aims.  相似文献   

16.
《Small Ruminant Research》2009,84(1-3):74-78
The cervical anatomy limits the use of trans-cervical artificial insemination (AI) and embryo transfer in ewes. Thus, the objective of the study was to evaluate the sub-arachnoid administration of ketamine as a tool to be used in cervical dilation of the ewe. The following experimental treatments were used: in Experiment 1, animals (n = 6) were treated with the sub-arachnoid administration of ketamine (KS, 1.5 mg kg−1); and in Experiment 2, one tablet of misoprostol was diluted in 1.5 ml saline and deposited near the cervical os, 5 h before the trial + oxytocin administered i.v. 5 min before the reproductive procedures (MO, 200 + 20 U.I., respectively). In Experiment 3, animals received sub-arachnoid ketamine + misoprostol/oxytocin (KSMO). The systemic effects, analgesia, sedation, and motor neuron block were evaluated before each experiment and at pre-determined time intervals thereafter. A subjective score system was used to assess pain and discomfort during the reproductive manipulations in the different experiments. The mean duration of analgesia in the sternal decubitus position without sedation was 30 ± 4 and 25 ± 7 min for the KS and KSMO treatments, respectively. All treatments provided sufficient cervical dilation for the passage of the insemination rod into the uterus. The ketamine sub-arachnoid treatment alone produced a complete cervical dilation, allowing easy passage of the rod. Further studies are needed to establish whether this anesthetic technique may interfere with fertility, pregnancy or lambing rate in ewes during AI or embryo transfer.  相似文献   

17.
In this paper, the authors made an attempt to measure appropriation of ecosystems more reasonably and effectively based on examining the advantages and disadvantages of emergy analysis and ecological footprint. By combining emergy analysis with ecological footprint (EF) in terms of spatial equivalent of energy productivity, a new method of solar space (SS) and its calculating framework was proposed, and some necessary parameters for this method of analysis were calculated. A case study was followed under this calculating framework for Yangzhou city, Jiangsu province, Eastern China, using the data of the year 2000. The main results are as follows: (1) The ecological space in Yangzhou city includes earth surface space and solar space, and their demands were bigger than their supply. In the year of 2000, the earth surface space had an absolute deficit of 2.3063E?02 Ga-ha per capita (global hectares), and the solar space had an absolute deficit of 1.4944E?04 Sa-ha per capita (solar hectares). (2) There was a relative ecological deficit of 3.68% in earth surface space, and that of 154.86% in solar space. (3) Only freshwater areas and built-up areas were in a state of surplus, and there was a relative ecological surplus of 82.66% for freshwater areas, being greater than that for built-up areas. (4) The ranking of absolute ecological deficit in a descending order was as follows: solar space > arable land > pasture > forest > marine area > garden land, while the relative ecological deficit was the following: solar space > pasture land > forest land > arable land > garden land, except marine areas.A qualitative comparison of methodology was made between solar space method and ecological footprint according to their capability to describe the temporal-spatial characteristics of ecosystems appropriation. Moreover, a quantitative comparison was also conducted to show their differences in applicability to the assessment of ecosystems appropriation. It was shown that the calculating results from solar space method were bigger than that from ecological footprint because the former supplemented additional items of appropriation omitted by the later and included some new items of indirect appropriation that were excluded by the later. It is found that the new measure of solar space operates well as an indicator of the city's appropriation to ecosystems.  相似文献   

18.
Automated microfluidic devices are a promising route towards a point-of-care autologous cell therapy. The initial steps of induced pluripotent stem cell (iPSC) derivation involve transfection and long term cell culture. Integration of these steps would help reduce the cost and footprint of micro-scale devices with applications in cell reprogramming or gene correction. Current examples of transfection integration focus on maximising efficiency rather than viable long-term culture. Here we look for whole process compatibility by integrating automated transfection with a perfused microfluidic device designed for homogeneous culture conditions. The injection process was characterised using fluorescein to establish a LabVIEW-based routine for user-defined automation. Proof-of-concept is demonstrated by chemically transfecting a GFP plasmid into mouse embryonic stem cells (mESCs). Cells transfected in the device showed an improvement in efficiency (34%, n = 3) compared with standard protocols (17.2%, n = 3). This represents a first step towards microfluidic processing systems for cell reprogramming or gene therapy.  相似文献   

19.
The purpose of this study was to determine the impact of the core to skin temperature gradient during incremental running to volitional fatigue across varying environmental conditions. A secondary aim was to determine if a “critical” core temperature would dictate volitional fatigue during running in the heat. 60 participants (n=49 male, n=11 female; 24±5 yrs, 177±11 cm, 75±13 kg) completed the study. Participants were uniformly stratified into a specific exercise temperature group (18 °C, 26 °C, 34 °C, or 42 °C) based on a 3-mile run performance. Participants were equipped with core and chest skin temperature sensors and a heart rate monitor, entered an environmental chamber (18 °C, 26 °C, 34 °C, or 42 °C), and rested in the seated position for 10 min before performing a walk/run to volitional exhaustion. Initial treadmill speed was 3.2 km h−1 with a 0% grade. Every 3 min, starting with speed, speed and grade increased in an alternating pattern (speed increased by 0.805 km h−1, grade increased by 0.5%). Time to volitional fatigue was longer for the 18 °C and 26 °C group compared to the 42 °C group, (58.1±9.3 and 62.6±6.5 min vs. 51.3±8.3 min, respectively, p<0.05). At the half-way point and finish, the core to skin gradient for the 18 °C and 26 °C groups was larger compared to 42 °C group (halfway: 2.6±0.7 and 2.0±0.6 vs. 1.3±0.5 for the 18 °C, 26 °C and 42 °C groups, respectively; finish: 3.3±0.7 and 3.5±1.1 vs. 2.1±0.9 for the 26 °C, 34 °C, and 42 °C groups, respectively, p<0.05). Sweat rate was lower in the 18 °C group compared to the 26 °C, 34 °C, and 42 °C groups, 3.6±1.3 vs. 7.2±3.0, 7.1±2.0, and 7.6±1.7 g m−2 min−1, respectively, p<0.05. There were no group differences in core temperature and heart rate response during the exercise trials. The current data demonstrate a 13% and 22% longer run time to exhaustion for the 18 °C and 26 °C group, respectively, compared to the 42 °C group despite no differences in beginning and ending core temperatures or baseline 3-mile run time. This capacity difference appears to result from a magnified core to skin gradient via an environmental temperature advantageous to convective heat loss, and in part from an increased sweat rate.  相似文献   

20.
Han SX  Wang L  Wu DQ 《Cancer epidemiology》2012,36(4):e201-e206
Background: studies investigating the associations between UDP-glucuronosyltransferase 1A7 (UGT1A7) gene polymorphisms and various carcinomas risk reported conflicting results. To derive a more precise estimation of the association, we have conducted a meta-analysis. Methods: data were collected from the following electronic databases: PubMed, Medline and Chinese Biomedical Literature Database, with the last report up to September 2011. Case–control studies containing available genotype frequencies of UGT1A7 were chose. The odds ratio (OR) and its 95% confidence interval (95%CI) were used to assess the strength of association. Results: a total of 22 separate case–control studies including 3852 cases and 5604 controls based on the search criteria were involved in this meta-analysis. The combined results based on all studies showed that there was a statistically significant link between UGT1A7*3 allele and cancer risk (OR = 1.31, 95%CI = 1.14–1.50, P = 0.0001). In the stratified analysis by racial descent, significant increased risk was found in Asian population for UGT1A7*3 allele (OR = 1.41, 95%CI = 1.22–1.63, P < 0.00001). No significant associations were found between the UGT1A7 polymorphism and cancer susceptibility among Caucasians and African-Americans. In the subgroup analysis by cancer types, significant associations were found in UGT1A7*2 allele (OR = 1.23, 95%CI = 1.06–1.43, P = 0.006) and *3 allele (OR = 1.51, 95%CI = 1.11–2.06, P = 0.009) for hepatocellular carcinoma, *3 allele for lung cancer (OR = 1.36, 95%CI = 1.11–1.68, P = 0.004) and for bladder cancer (OR = 1.50, 95%CI = 1.09–2.07, P = 0.01). Conclusions: This meta-analysis suggests that the UGT1A7*3 allele is a risk factor for cancer among Asians, especially for hepatocellular carcinoma.  相似文献   

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