Hydrological regime alteration and ecological flow evaluation in mountain rivers

In the Alpine region, the hydropower production has caused alterations in the hydrological regime of most rivers, due to the massive withdrawal of water and to the construction of dams and reservoirs, which modify the natural flow duration curve of the river. These alterations may result in a decrease in hydro-morphological and ecological quality of the river and limitations are considered, usually expressed as an ecological flow that has to be guaranteed. Many types of approaches are suggested in literature to define this flow, taking into account hydrological, physical, chemical and biological factors. Methods based only on hydraulic/hydrological parameters are often preferred, due to simplicity and robustness. More, with methods based only on hydrological parameters is simpler to take into account changes in river regime due to anthropic activities. However, some ecological issues are also important for river quality, such as the lentic-lotic characteristics of flow, but they are difficult to be expressed in crisp numerical values. In the last years more complex methods have been proposed as an alternative to hydrological models. One of them is the method CARAVAGGIO (Core Assessment of River hAbitat VAlue and hydro-morpholoGIcal cOndition). Although this model is able to take into account a great number of different aspects, its application is not always possible due to the difficulties in entering the river in some sites. In this paper a procedure able to merge the ease of use of hydrological methods and the multi-factor approach of CARAVAGGIO is proposed. Ecological flow is estimated from basic hydrological information, using a simple set of coefficients to take into account other quality issues, particularly the lentic-lotic features of flow regime. Application to a case study in the Province of Verbano-Cusio-Ossola, in the north-western part of Piedmont Region in Italy, is presented

Ecosistemi di acque interne e di transizione

In questo contributo la vulnerabilità degli ecosistemi acquatici ai cambiamenti climatici è analizzata in relazione ai meccanismi di organizzazione e mantenimento della biodiversità e dei processi ecosistemici. Dai processi degli ecosistemi derivano funzioni che forniscono una serie di benefici o servizi per il genere umano (Daily et al., 2009). Tali servizi sono in larga misura dipendenti dalle componenti biologiche degli ecosistemi86. Negli ecosistemi acquatici i processi biogeochimici (ad es. denitrificazione batterica e assimilazione da parte della vegetazione acquatica), garantiscono l’abbattimento dei nutrienti, una funzione ecosistemica che produce il servizio di depurazione dell’acqua. Altri servizi sono la laminazione delle piene, la ricarica degli acquiferi, la regolazione del microclima locale, la produzione di risorse alimentari quali pesci, crostacei, ecc. (Jones, 2013). Le alterazioni degli ecosistemi, in particolare la perdita di specie e la diminuzione della biodiversità danneggiano questi servizi, con ricadute anche di tipo economico(si pensi, ad esempio, ai costi della depurazione dell’acqua destinata al consumo umano)

The climatic characteristics of extreme precipitations for short-term intervals in the watershed of Lake Maggiore

Alpine and Mediterranean areas are undergoing a profound change in the typology and distribution of rainfall. In particular, there has been an increase in consecutive nonrainy days, and an escalation of extreme rainy events. The climatic characteristic of extreme precipitations over shortterm intervals is an object of study in the watershed of Lake Maggiore, the second largest freshwater basin in Italy (located in the north-west of the country) and an important resource for tourism, fishing and commercial flower growing. The historical extreme rainfall series with high-resolution from 5 to 45 min and above: 1, 2, 3, 6, 12 and 24 h collected at different gauges located at representative sites in the watershed of Lake Maggiore, have been computed to perform regional frequency analysis of annual maxima precipitation based on the Lmoments approach, and to produce growth curves for different return-period rainfall events. Because of different rainfallgenerating mechanisms in the watershed of Lake Maggiore such as elevation, no single parent distribution could be found for the entire study area. This paper concerns an investigation designed to give a first view of the temporal change and evolution of annual maxima precipitation, focusing particularly on both heavy and extreme events recorded at time intervals ranging from few minutes to 24 h and also to create and develop an extreme storm precipitation database, starting from historical sub-daily precipitation series distributed over the territory. There have been two-part changes in extreme rainfall events occurrence in the last 23 years from 1987 to 2009. Little change is observed in 720 min and 24- h precipitations, but the change seen in 5, 10, 15, 20, 30, 45, 60, 120, 180 and 360 min events is significant. In fact, during the 2000s, growth curves have flattened and annual maxima have decreased

Early autonomic dysfunction in glucose-tolerant but insulin-resistant offspring of type 2 diabetic patients

In type 2 diabetes, both insulin resistance and hyperglycemia are considered responsible for autonomic dysfunction, but the specific role of these two abnormalities is not clear. To test the specific role of insulin resistance on autonomic dysfunction, we studied 69 glucose-tolerant offspring of type 2 diabetic patients, comparing the most insulin-resistant tertile (IR) with the most insulin-sensitive tertile (IS) and comparable control subjects, all undergoing the oral glucose tolerance test, impedentiometry, 24-hour blood pressure and ECG monitoring, and an intravenous glucose tolerance test (IVGTT) followed by a euglycemic hyperinsulinemic clamp, with continuous blood pressure and ECG measurements. Sympathovagal balance was evaluated as low- to high-frequency ratio (LF: HF) by spectral analysis on R-R intervals. The change of systolic and diastolic blood pressure was calculated as [(day-night/ d)] x 100. In IR, the changes of systolic and diastolic blood pressure were significantly lower versus IS (9.2 +/- 5.0% versus 12.4 +/- 3.6%, P < 0.02; 13.2 +/- 6.5% versus 17.4 +/- 5.2%, P < 0.02). During the night, LF: HF fall was reduced in IR ( 43.1 +/- 21.0 versus 61.4 +/- 16.9, P < 0.02). Hyperinsulinemia ( IVGTT) rapidly and significantly increased LF: HF in IR (4.9 +/- 3.3 versus basal: 2.3 +/- 1.4, P = 0.03) but not in IS. In offspring of type 2 diabetic patients with normal glucose tolerance and normal blood pressure values, insulin resistance is associated with abnormal control of blood pressure and sympathetic activation. Insulin resistance may therefore be responsible for some early derangements of the autonomic nervous tone control and thus contributes to increase the incidence of arterial hypertension and/or diabetes

Vaginal bacterial and fungal flora in pregnant diabetic and non-diabetic women: a multi center observational case-control study

Objective: We evaluated the prevalence of cervicovaginal Bacteria, group B Streptococcus (GBS), Gardnerella vaginalis (GV), Candida spp., Chlamydia trachomatis (CT), Mycoplasma hominis (MH) and Ureaplasma urealyticum (UU) in pregnant women with and without diabetes mellitus (DM). Materials and method: Cervicovaginal swabs were gathered from 473 pregnant patients divided into 127 diabetic and 346 non-diabetic. The results were correlated to gestational age, parity and glycemic control. Results: A higher prevalence of MH/UU (P=0.012) was found in the diabetic patients. After the 28th weeks of pregnancy the prevalence for all investigated microorganisms appeared similar except for MH/UU (P=0.014). In multigravida were there statistically differences between two groups in testing for Bacteria (P=0.015) and for MH/UU (P=0.037). The diabetic condition correlated to the state of multigravida in cases positive for Candida spp (P=0.049) and in those testing positive for at least one microorganism (P=0.043). Pregnant with a blood glucose > 92 have twice the risk of being positive to a single microbiological test than those with better glycemic control. Conclusions: The higher prevalence of MH/UU after the 28 th weeks can be explained with the physiological reduced insulin tolerance characteristic of this gestational period. Among the diabetic testing positive to Candida spp the statistically significant association was observed only in multigravida condition. These data suggest that diabetic multigravida are at increased risk for Candida spp infection in relation to the improper glycemic control

Cervicovaginal bacteria and fungi in pregnant diabetic and non-diabetic women. a multicenter observational cohort study

Abstract. – OBJECTIVE: We evaluated the prevalence of cervicovaginal Bacteria, group B Streptococcus (GBS), Gardnerella vaginalis (GV), Candida spp., Chlamydia trachomatis (CT), Mycoplasma hominis (MH) and Ureaplasma urealyticum (UU) in pregnant women with and without diabetes mellitus (DM). PATIENTS AND METHODS: Cervicovaginal swabs were gathered from 473 pregnant patients divided into 127 diabetic and 346 non-diabetic. The results were correlated to gestational age, parity and glycemic control. RESULTS: A higher prevalence of MH/UU (p=0.012) was found in the diabetic patients. After the 28th week of pregnancy, the prevalence for all investigated microorganisms appeared similar except for MH/UU (p=0.014). In multigravida, there were statistical differences between two groups in testing for Bacteria (p=0.015) and for MH/UU (p=0.037). The diabetic condition correlated to the state of multigravida in cases positive for Candida spp. (p=0.049) and in those testing positive for at least one microorganism (p=0.043). Pregnant with a blood glucose > 92 have twice the risk of being positive to a single microbiological test than those with better glycemic control. CONCLUSIONS: The higher prevalence of MH/ UU after the 28th weeks can be explained with the physiologically reduced insulin tolerance characteristic of this gestational period. Among the diabetic testing positive to Candida spp. the statistically significant association was observed only in multigravida condition. These data suggest that diabetic multigravida women are at increased risk for Candida spp. infection in relation to the improper glycemic control

Ecosistemi di acque interne e di transizione

La valutazione dello stato di conservazione di biodiversità, funzioni e servizi degli ecosistemi di acque interne e la stima della loro vulnerabilità ai cambiamenti climatici sono affrontate considerando tipologie omogenee di ecosistemi acquatici, alla scala integrata del bacino idrografico e della zona di transizione adiacente. Gli ecosistemi acquatici sono ripartiti, secondo uno schema tradizionale, in: bacini fluviali, laghi, zone umide e acque lentiche85 di piccole dimensioni, ecosistemi dipendenti dalle acque sotterranee (Groundwater Dependent Ecosystems - GDE) e ambienti di transizione a mare. I bacini fluviali e i laghi sono inoltre analizzati nel contesto della regione geografica cui appartengono, assumendo che vi siano associate diverse pressioni e minacce derivanti dai cambiamenti climatici. I cambiamenti climatici hanno effetti diretti sulla fenologia e sulla distribuzione delle specie che si manifestano in seguito a modificazioni della durata delle fasi di crescita, anticipazione o ritardo nelle migrazioni, sfasamento dei cicli vitali di predatore e preda, e migrazione verso nord e verso monte delle specie sensibili all’aumento di temperatura. Negli ecosistemi acquatici queste perturbazioni sono causate non solo dall’aumento della temperatura, ma anche dalle variazioni del regime idrologico e delle proprietà fisiche delle masse d’acqua. Tra gli ecosistemi a maggiore vulnerabilità si annoverano le acque lentiche di piccole dimensioni, i GDE e i laghi d’alta quota, e i corsi d’acqua appenninici e delle isole maggiori, sui quali già insistono pressioni importanti per l’elevato tasso di sfruttamento del territorio e delle risorse idriche. La vulnerabilità dei grandi corsi d’acqua dipende dall’interazione tra le pressioni locali (uso del suolo, urbanizzazione, alterazioni idro-morfologiche), le variazioni del regime idrologico e la gestione delle risorse idriche. Attualmente si segnalano problemi legati al dissesto idromorfologico dei corsi d’acqua, al deflusso residuo a valle delle derivazioni idriche, alle variazioni improvvise e intense delle portate dovute all’esercizio delle centrali idroelettriche (hydropeaking), all’inquinamento delle acque, alla perdita di specie indigene e alla crescente diffusione di specie aliene. Queste situazioni potrebbero essere amplificate dalle variazioni del regime idrologico indotte dai cambiamenti climatici. I grandi laghi subalpini profondi sono regolati e costituiscono la più importante riserva di acqua dolce in Italia. Negli ultimi decenni si sono osservate condizioni critiche per il bilancio termico e la conseguente stratificazione della colonna d’acqua: l’aumento della temperatura atmosferica ha già causato una notevole riduzione della frequenza del rimescolamento delle intere masse d’acqua (oligomissi) e potrebbe portare a un rimescolamento limitato ai soli strati superficiali (meromissi). Le condizioni di meromissi sono in genere accompagnate dall’esaurimento dell’ossigeno disciolto nelle acque di fondo e da notevoli alterazioni della composizione delle comunità lacustri. Nel lungo termine, la diminuzione degli apporti nivali e glaciali e l’aumento dei prelievi potrebbero determinare oscillazioni del livello idrico con gravi impatti anche sulle zone litoranee di basso fondale. Condizioni di particolare vulnerabilità sono previste per i laghi dell’Italia centrale, in particolare per quelli poco profondi come il Lago Trasimeno, nei quali si stanno verificando l’interramento delle zone litoranee, l’aumento delle concentrazioni dei soluti e il riscaldamento delle acque. Nei laghi artificiali dell’Italia meridionale e delle isole, la diminuzione delle precipitazioni e l’aumento della temperatura, combinate con un maggiore consumo idrico, potrebbero accentuare le variazioni di livello, favorendo così il peggioramento della qualità delle acque e l’affermazione di specie invasive e di cianobatteri tossici. Le acque di transizione (foci fluviali e lagune costiere) sono esposte alle variazioni del regime idrologico dei bacini di monte, all’innalzamento del livello marino e all’aumento della temperatura. Trattandosi di sistemi a bassa profondità, sono attesi effetti particolarmente marcati nelle comunità bentoniche, con comparsa di fioriture di macroalghe, microalghe tossiche e cianobatteri e scomparsa delle specie animali maggiormente sensibili. Le opere di difesa idraulica a protezione dei centri abitati e delle zone agricole subsidenti potrebbero fare aumentare il confinamento delle aree lagunari interne, con rischi crescenti di stagnazione e anossia delle acque, condizioni che comportano la perdita di specie sensibili al tenore di ossigeno e alla temperatura. Complessivamente, si ritiene che le tendenze evolutive degli ecosistemi lagunari possano essere sfavorevoli per le specie native a vantaggio di quelle esotiche, con possibili impatti anche sulle attività di pesca e acquacoltura. Nelle foci fluviali, nei periodi di secca si potrà verificare la risalita del cuneo salino, un fenomeno che si è già manifestato in modo significativo in anni particolarmente siccitosi, ad esempio dal 2003 al 2007. Nella maggior parte degli ambienti acquatici considerati, al crescere della temperatura e della durata della stagnazione delle masse idriche potranno aumentare il metabolismo microbico e l’eterotrofia, con possibili retroazioni sulle emissioni di gas clima-alteranti (CO2, N2O e CH4)

Continuous subcutaneous insulin infusion (CSII) in inpatient setting: unmet needs and the proposal of a CSII unit

Continuous subcutaneous insulin infusion (CSII) represents an increasingly popular method of treating diabetes. Patients with diabetes are often hospitalized, and current data indicate that inpatient hyperglycemia results in poorer outcomes. When patients on insulin pump therapy require hospitalization, practitioners caring for them face the issue of how to manage the inpatient care of these patients. We believe that patients using insulin pumps can safely have their therapy transitioned when hospitalized. Moreover, CSII during hospitalization should be regarded not only as a fundamental tool in patients already on insulin pump therapy, but also as an effective method to obtain euglycemia, in critically ill patients. However, a standard policy on CSII use during hospitalization is still lacking, and literature data are inconclusive about the benefits of insulin pump on glycemic homeostasis, in hospitalized patients. We suggest that a CSII unit should be activated inside the hospital, in order to increase compliance with required procedures and to properly address the unmet needs of CSII in inpatient setting