Effects of urban catchment characteristics on combined sewer overflows.

Pollution from Combined Sewer Overflows (CSOs) cause diffuse environmental problems, which are still not satisfactorily addressed by current management practices. In this study, a sensitivity analysis was conducted on several CSO environmental impact indicators, with respect to parameters that characterise climate, urban catchment and the CSO structure activation threshold. The sensitivity analysis was conducted by running 10000 simulations with the Storm Water Management Model, using a simplified modelling approach. The indicators were calculated at yearly scale to evaluate overall potential effects on water bodies. The results could be used to estimate pollution load ranges, known the values of the input parameters, and to investigate suitable strategies to reduce pollution of the receiving water bodies. The percentage of impervious surface of the catchment was found the most influent parameter on all the indicators, and its reduction can contain the discharged pollutant mass. The activation threshold, instead, resulted the second least influent parameter on all the indicators, suggesting that its regulation alone would not be a suitable strategy to reduce CSO pollution. However, along with the reduction of the imperviousness, its increase could effectively decrease the concentration of pollutant in the overflow. The results also indicate that neither adopting sustainable urban drainage practices, nor interventions on the CSO device, significantly affect the frequency of the overflows. Therefore, restricting this latter was found to be ineffective for the reduction of both the discharged pollutant mass and the concentration of pollutant in the overflow.

Prototype of an IoT-Based Low-Cost Sensor Network for the Hydrological Monitoring of Landslide-Prone Areas.

Steep slopes covered by loose unsaturated pyroclastic deposits widely dispersed in Campania, Southern Italy, are often subjected to shallow landslides that turn into fast debris flows causing a large amount of damage and many casualties, triggered by heavy and persistent precipitation. The slope of Cervinara, located around 40 km northeast of Naples, was involved in a destructive flowslide between 15 and 16 December 1999, triggered by a rain event of 325 mm in 48 h. Hydrometeorological monitoring activities have been carried out near the landslide scarp of 1999 since 2017 to assess the water balance and to identify major hydrological processes involving the cover and the shallow groundwater system developing in the upper part of the underlying limestone fractured bedrock. Since 1 December 2022, a remotely accessible low-cost network has been installed to expand the field hydrological monitoring. The use of a network of low-cost capacitive sensors, communicating within the domain of Internet of Things (IoT) technology, aiming at dispersed monitoring of soil moisture, has been tested. Specifically, the tested prototype network allows measurements of the soil water content at two different points, communicating through a Wi-Fi-based IoT system using ESP32 boards. The ThingSpeakTM IoT platform has been used for remote field data visualization. Based on the obtained results, the prototype of this IoT-based low-cost network shows the potential to expand the amount of hydrological data, suitable for setting up early warning systems in landslide-prone areas.

Exposure To Climate Risk: A Case Study For Coffee Farming In The Region Of Alta Mogiana, São Paulo.

Studies around the world show an increase in global average temperatures, with a consequent increase in extreme events and changes in the distribution of precipitation, causing a decrease in agricultural production and changes in planting areas. This study analyzed the exposure to climate risk that the coffee crop in the region of Alta Mogiana/SP, Brazil has been presenting in the past thirty years (1991-2021). Time series of daily data of maximum and minimum temperature and precipitation were used. By the statistical tests we observed a trend of increase in maximum temperatures daily of approximately 1.4°C and minimum daily of 0.8°C in the municipalities of the region and a trend towards a decrease in precipitation of 0.9 mm daily, indicating greater exposure of the coffee crop in the region to climate risk and increased vulnerability for the coffee producer. In view of these analyses, a literature review was carried out, suggesting agroforestry systems and mechanical irrigation as the most promising strategies to manage climate risk in coffee plantations. In addition, drought-resistant cultivars, training courses for farmers, increased rural insurance, and nutritional control of the plants can also be considered efficient options for climate exposure in coffee plantations from Alta Mogiana.

Synthesis of α/ß dipeptides containing linear or cyclic α-dehydro-ß-amino acids as scaffolds for bioactive compounds.

The synthesis of α/ß dipeptides containing linear or cyclic α-dehydro-ß-amino acids has been performed starting from alkylidene acetacetamides, which were obtained from α-amino esters via Ir-catalyzed allylic amination. Differently hindered carbonates were synthesized via a protocol involving chemoselective Luche's reduction, acylation, and allylic amination. Depending on the nature of the selected α-amino acid, we observed strong influence on the product regiochemistry due to the carbonate size and the amino-acid side chain. In particular, complete regioselectivity was observed in the aminic allylation of carbonates deriving from amino acids possessing a methylene unit in ß-position. On the contrary, methyl carbonates deriving from ß-branched amino acid afforded different results depending on the hindrance of the carbonate. Moreover, spontaneous cyclization was observed for carbamate-containing intermediates, allowing to obtain peptidomimetic polyfunctionalized dihydropyrimidine-2,4-dione. Finally, by inverting the order of reduction/acylation steps on the starting alkylidene acetoacetamides, the formation of polyfunctionalized 1,3-oxazinane-2,4-dione was obtained demonstrating the wide applications of these substrates for the preparation of bioactive peptidomimetics.

Experimental Determination of TDR Calibration Relationship for Pyroclastic Ashes of Campania (Italy).

Time domain reflectometry (TDR) is one of the most widely used techniques for indirect determination of soil volumetric water content (θ). TDR measures the relative dielectric constant (εr) which, in a three-phase system like the soil, depends on water, air, and solid matrix dielectric constants. Since dielectric constant of water is much larger than the other two, εr of bulk soil mainly depends on water content. In many cases, the application of TDR requires a specific calibration of the relationship θ(εr) to get quantitatively accurate estimates of soil water content. In fact, the relationship θ(εr) is influenced by various soil properties, such as clay content, organic matter content, bulk density, and aggregation. Numerous studies have shown that pyroclastic soils often exhibit a peculiar dielectric behavior. In Campania (Southern Italy) wide mountainous areas are covered by layered pyroclastic deposits of ashes (loamy sands) and pumices (sandy gravels), often involved in the triggering of landslides induced by rainwater infiltration. Reliable field measurements of water content of such soils are therefore important for the assessment of landslide risk. Hence, in this paper, the θ(εr) relationship has been experimentally determined on samples of typical pyroclastic soil of Campania, collected around Sarno, reconstituted with different porosities. The aim of the study is to identify specific calibration relationships for such soils based not only on empirical approaches. In this respect, a three-phase dielectric mixing model with a variable exponent is introduced, and the variable value of the exponent is related to the different dielectric properties of bond and free water within the soil pores.

Scaling-Laws of Flow Entropy with Topological Metrics of Water Distribution Networks.

Robustness of water distribution networks is related to their connectivity and topological structure, which also affect their reliability. Flow entropy, based on Shannon's informational entropy, has been proposed as a measure of network redundancy and adopted as a proxy of reliability in optimal network design procedures. In this paper, the scaling properties of flow entropy of water distribution networks with their size and other topological metrics are studied. To such aim, flow entropy, maximum flow entropy, link density and average path length have been evaluated for a set of 22 networks, both real and synthetic, with different size and topology. The obtained results led to identify suitable scaling laws of flow entropy and maximum flow entropy with water distribution network size, in the form of power-laws. The obtained relationships allow comparing the flow entropy of water distribution networks with different size, and provide an easy tool to define the maximum achievable entropy of a specific water distribution network. An example of application of the obtained relationships to the design of a water distribution network is provided, showing how, with a constrained multi-objective optimization procedure, a tradeoff between network cost and robustness is easily identified.

The Impacts of Heating Strategy on Soil Moisture Estimation Using Actively Heated Fiber Optics.

Several recent studies have highlighted the potential of Actively Heated Fiber Optics (AHFO) for high resolution soil moisture mapping. In AHFO, the soil moisture can be calculated from the cumulative temperature ( T cum ), the maximum temperature ( T max ), or the soil thermal conductivity determined from the cooling phase after heating ( λ ). This study investigates the performance of the T cum , T max and λ methods for different heating strategies, i.e., differences in the duration and input power of the applied heat pulse. The aim is to compare the three approaches and to determine which is best suited to field applications where the power supply is limited. Results show that increasing the input power of the heat pulses makes it easier to differentiate between dry and wet soil conditions, which leads to an improved accuracy. Results suggest that if the power supply is limited, the heating strength is insufficient for the λ method to yield accurate estimates. Generally, the T cum and T max methods have similar accuracy. If the input power is limited, increasing the heat pulse duration can improve the accuracy of the AHFO method for both of these techniques. In particular, extending the heating duration can significantly increase the sensitivity of T cum to soil moisture. Hence, the T cum method is recommended when the input power is limited. Finally, results also show that up to 50% of the cable temperature change during the heat pulse can be attributed to soil background temperature, i.e., soil temperature changed by the net solar radiation. A method is proposed to correct this background temperature change. Without correction, soil moisture information can be completely masked by the background temperature error.

A new method to investigate the intrusion of water into porous hydrophobic structures under dynamic conditions.

The intrusion of water into the pores of hydrophobic materials is investigated by means of a dynamic flow system. The porous hydrophobic material is packed into a stainless steel chromatographic column, and water is flushed through by means of a high-pressure pump. Back-pressure control is provided by flow restrictors after the column. The applied pressure forces the water to penetrate the pores of the hydrophobic material. The water volume contained in the column, as a function of the applied pressure, reflects the degree of wetting of the solid by water. This volume is determined by measuring, through a mass spectrometer, the retention time of deuterium oxide injected in the column. The method is applied with alkyl-modified (n-octyl and n-octadecyl) and perfluorinated (alkyl and phenyl) silica surfaces. The information gathered by this study may contribute to explain the retention behavior of reversed-phase chromatographic columns when used under highly aqueous mobile-phase conditions.

A combined kinetic and thermodynamic approach for the interpretation of continuous-flow heterogeneous catalytic processes.

The heterogeneous proline-catalyzed aldol reaction was investigated under continuous-flow conditions by means of a packed-bed microreactor. Reaction-progress kinetic analysis (RPKA) was used in combination with nonlinear chromatography for the interpretation, under synthetically relevant conditions, of important mechanistic aspects of the heterogeneous catalytic process at a molecular level. The information gathered by RPKA and nonlinear chromatography proved to be highly complementary and allowed for the assessment of optimal operating variables. In particular, the determination of the rate-determining step was pivotal for optimizing the feed composition. On the other hand, the competitive product inhibition was responsible for the unexpected decrease in the reaction yield following an apparently obvious variation in the feed composition. The study was facilitated by a suitable 2D instrumental arrangement for simultaneous flow reaction and online flow-injection analysis.

Comparison of topological, empirical and optimization-based approaches for locating quality detection points in water distribution networks.

The positioning of quality detection points as well as the frequency of sampling is a crucial aspect for the implementation of Water Safety Plans (WSPs), which have been proposed worldwide to ensure water quality and to minimize the risk from contamination in water distribution networks (WDNs). In this regard, some international legislations and best practices about quality of drinking water suggest very fine sampling frequencies, but they do not specify where the detection points should be located in a WDN. In this paper, three different approaches, based on empiricism, optimization and topology, respectively, were applied to locate detection quality points in a WDN. The comparison highlighted that empirical approach commonly adopted by water utility practitioners is unsatisfactory. The optimization-based approach, although performing significantly better, is difficult to apply, since it requires a calibrated hydraulic model. The topological approach, based on the use of the betweenness centrality and not requiring any hydraulic information and simulation, proves to be effective, and it can be easily adopted by water utilities to identify the location for quality detection points, due to its simplicity compared with the optimization-based approach.

Integrin-mediated adhesive properties of neutrophils are reduced by hyperbaric oxygen therapy in patients with chronic non-healing wound.

In recent years, several studies suggested that the ability of hyperbaric oxygen therapy (HBOT) to promote healing in patients with diabetic ulcers and chronic wounds is due to the reduction of inflammatory cytokines and to a significant decrease in neutrophils recruitment to the damaged area. α4 and ß2 integrins are receptors mediating the neutrophil adhesion to the endothelium and the comprehension of the effects of hyperbaric oxygenation on their expression and functions in neutrophils could be of great importance for the design of novel therapeutic protocols focused on anti-inflammatory agents. In this study, the α4 and ß2 integrins' expression and functions have been evaluated in human primary neutrophils obtained from patients with chronic non-healing wounds and undergoing a prolonged HBOT (150 kPa per 90 minutes). The effect of a peptidomimetic α4ß1 integrin antagonist has been also analyzed under these conditions. A statistically significant decrease (68%) in ß2 integrin expression on neutrophils was observed during the treatment with HBO and maintained one month after the last treatment, while α4 integrin levels remained unchanged. However, cell adhesion function of both neutrophilic integrins α4ß1 and ß2 was significantly reduced 70 and 67%, respectively), but α4ß1 integrin was still sensitive to antagonist inhibition in the presence of fibronectin, suggesting that a combined therapy between HBOT and integrin antagonists could have greater antinflammatory efficacy.

Weighted spectral clustering for water distribution network partitioning.

In order to improve the management and to better locate water losses, Water Distribution Networks can be physically divided into District Meter Areas (DMAs), inserting hydraulic devices on proper pipes and thus simplifying the control of water budget and pressure regime. Traditionally, the water network division is based on empirical suggestions and on 'trial and error' approaches, checking results step by step through hydraulic simulation, and so making it very difficult to apply such approaches to large networks. Recently, some heuristic procedures, based on graph and network theory, have shown that it is possible to automatically identify optimal solutions in terms of number, shape and dimension of DMAs. In this paper, weighted spectral clustering methods have been used to define the optimal layout of districts in a real water distribution system, taking into account both geometric and hydraulic features, through weighted adjacency matrices. The obtained results confirm the feasibility of the use of spectral clustering to address the arduous problem of water supply network partitioning with an elegant mathematical approach compared to other heuristic procedures proposed in the literature. A comparison between different spectral clustering solutions has been carried out through topological and energy performance indices, in order to identify the optimal water network partitioning procedure.

Synthetic oligonucleotide separations by mixed-mode reversed-phase/weak anion-exchange liquid chromatography.

Synthetic oligonucleotides gain increasing importance in new therapeutic concepts and as probes in biological sciences. If pharmaceutical-grade purities are required, chromatographic purification using ion-pair reversed-phase chromatography is commonly carried out. However, separation selectivity for structurally closely related impurities is often insufficient, especially at high sample loads. In this study, a "mixed-mode" reversed-phase/weak anion exchanger stationary phase has been investigated as an alternative tool for chromatographic separation of synthetic oligonucleotides with minor sequence variations. The employed mixed-mode phase shows great flexibility in method development. It has been run in various gradient elution modes, viz. one, two or three parameter (mixed) gradients (altering buffer pH, buffer concentration, and organic modifier) to find optimal elution conditions and gain further insight into retention mechanisms. Compared to ion-pair reversed-phase and mere anion-exchange separation, enhanced selectivities were observed with the mixed-mode phase for 20-23 nucleotide (nt) long oligonucleotides with similar sequences. Oligonucleotides differing by 1, 2 or 3 nucleotides in length could be readily resolved and separation factors for single nucleotide replacements declined in the order Cytosine (C)/Guanine (G)>Adenine (A)/Guanine∼Guanine/Thymine (T)>Adenine/Cytosine∼Cytosine/Thymine>Adenine/Thymine. Selectivities were larger when the modification was at the 3' terminal-end, declined when it was in the middle of the sequence and was smallest when it was located at the 5' terminus. Due to the lower surface area of the 200Špore size mixed-mode stationary phase compared to the corresponding 100Šmaterial, lower retention times with equal selectivities under milder elution conditions were achievable. Considering high sample loading capacities of the mixed-mode anion-exchanger phase, it should have great potential for chromatographic oligonucleotide separation and purification.

Bloodless surgery in geriatric surgery.

In bloodless surgery a series of measures has to be implemented to reduce the perioperative need for transfusion of whole blood or its components. Jehovah's Witness are the most representative group of patients opting for bloodless surgery as their faith follows strict believes that prohibits receiving blood. Geriatric patients requiring bloodless surgery are even more delicate and represent a challenge for surgeons. The physiological response of the over 65 year population to decreased hemoglobin level is slower and less effective than in young and adult patients. Herby we describe the perioperative protocol implemented in our surgical Department offered to geriatric Jehovah's Witness patients. Preoperative optimization of the patients is the key step in the preparation period. Intraoperative anesthetic and surgical measures are also required along with a strict postoperative follow-up. From our experience, bloodless surgery is feasible in the geriatric population as long as it is performed in specialized centers where a multidisciplinary team is prepared to specifically manage this scenario. Rigorous patients selection and preparation are mandatory.

Staples versus subcuticular closure in cervicotomy incisions.

Collar transverse incision is the typical surgical access for operations on thyroid and parathyroids. The cosmetic outcome resulting from its closure is of paramount importance given its anatomical exposure. The traditional methods of closure include metal clips, subcuticular stitch and glue. In this study we evaluated the cosmetic results on 10 patients who had their cervicotomy wound closed with clips comparing it to a second group of 10 patients who had the same incision closed with subcuticular stitch. The cosmetic outcome was evaluated with a questionnaire answered by the patients, by the operating surgeon and by a surgical nurse who was blinded to the technique used. The results of the questionnaire were grossly similar with no differences in the two groups. Only two complications were recorded in the subcuticular group. Both the techniques associate to similar cosmetic outcome, and the choice between the two should be left to the surgeon's personal preference.

Geometric characterization of straight-chain perfluorohexylpropyl adsorbents for high performance liquid chromatography.

The geometric characterization of porous adsorbents used as stationary phases in high performance liquid chromatography is a key aspect for the understanding and the description of retention mechanisms. Herein, we present a study aimed at describing the geometric characteristics of alkyl-perfluorinated silica stationary phases by employing chromatographic and non-chromatographic techniques. This study shows that, under typical chromatographic conditions, the perfluorohexylpropyl straight chains grafted to the silica surface assume a compact arrangement. As perfluorinated stationary phases are highly hydrophobic, their wetting behavior in water was investigated. To this end, a novel approach based on tracer pulse chromatography with pure water as the mobile phase and deuterium oxide as the labeled marker was employed. Experimentally it was found that, unless a high back-pressure is applied, water is expelled by the pores of the adsorbent. On the other hand, wetting can be significantly improved if 5-10% (v/v) of organic modifier is added to the mobile phase. The practical consequences of limited wettability are discussed, in particular with reference to fluorous-SPE (F-SPE) applications.