Hypolimnetic withdrawal coupled with oxygenation as lake restoration measures : the successful case of Lake Varese (Italy)

Lake Varese is a relatively small lake, belonging to the drainage basin of lake Maggiore (northern Italy). It has had a long history (since 1960s) of water quality deterioration as the result of cultural eutrophication. In 1967 a restoration project was designed, including a sewerage network, an O-ring sewage diversion system, and a centralised wastewater treatment plant with phosphorus and nitrogen control. Since the 1990's, the lake has been the object of a cooperative research program supported by the European Commission, the Italian Ministry of the Environment, the Lombardy Region, and the Varese Province. The subsequent studies revealed that the lake responded to the decreased external nutrient loads. Besides, mathematical models predicted a rather long period (30 years) to attain the restoration goal, recognising the importance of internal P loading from sediments. Also, it was predicted that the application of in-lake measures would be beneficial in accelerating lake recovery. Recently, two measures have been suggested, i.e. hypolimnetic withdrawal in the deepest section (maximum depth: 26 m) and oxygenation in the shallower section, during summer stratification. Lake Varese constitutes the first case in Italy where in-lake methods are used to counteract the problems caused by excessive nutrient enrichment in a relative large system (lake surface: 14.52 km2). In this paper, preliminary results of the first two years of operation (2000/2001) are summarised. The results are greatly encouraging. Lake water quality characteristics are as follows: Secchi transparency increased from 3.2 m to 4.9 m; annual mean total P concentrations decreased from 180 mg/m3 to 70 mg/m3; average chlorophyll values decreased from 40 mg/m3 to 17 mg/m3; the frequency of nuisance algal blooms declined to half in comparison to the 1990's and the algal density declined by a factor of 4, and anoxia periods decreased in time and space. Moreover, it has been evaluated that nutrient loads from lake Varese, due to the selected water discharges, did not affect the total nutrient budget of lake Maggiore and the downstream water quality.El lago Varese es un lago relativamente pequeño, situado en la cuenca de drenaje del lago Maggiore (norte de Italia). Presenta una larga historia (desde los años 60) de degradación de la calidad del agua como resultado de una eutrofización cultural. En 1967 se diseñó un proyecto de restauración, incluyendo una red de alcantarillado, un sistema en anillo de desvío de aguas residuales, y una planta centralizada de tratamiento de aguas residuales con control de fósforo y nitrógeno. Desde los años 90, el lago ha sido objeto de un programa de cooperación científica financiado por la Comisión Europea, el Ministerio de Medio Ambiente de Italia, la Región de Lombardy y la provincia de Varese. Los estudios resultantes mostraron la respuesta del lago a la disminución de la carga de nutrientes externa. Además, los modelos matemáticos predijeron un período bastante largo (30 años) para lograr el objetivo de restauración, reconociendo la importancia de la carga interna de P de los sedimentos. También, se predijo que la aplicación de medidas en el propio lago sería beneficiosa en la aceleración de la recuperación del lago. Recientemente, se han propuesto dos medidas, i.e. drenaje hipolimnético en la cubeta más profunda (profundidad máxima: 26 m) y oxigenación en la zona más somera, durante la estratificación estival. El lago Varese constituye el primer caso en Italia donde se han adoptado medidas en el propio lago para contrarrestar los problemas causados por un enriquecimiento excesivo de nutrientes en un sistema relativamente grande (superficie del lago: 14.52 km2). En este artículo se resumen los resultados preliminares de los dos primeros años de actuación (2000/2001). Los resultados son enormemente alentadores. Las características de la calidad del agua del lago son las siguientes: la transparencia del Secchi aumentó de 3.2 a 4.9 m; las concentraciones medias anuales de P total disminuyeron de 180 mg/m3 a 70 mg/m3; los valores medios de clorofila disminuyeron de 40 mg/m3 a 17 mg/m3; la frecuencia de florecimiento de algas se redujo a la mitad en comparación con los años 90 y la densidad de algas se dividió por un factor de 4, y los períodos de anoxia disminuyeron en el tiempo y en el espacio. Además, se ha comprobado que la carga de nutrientes procedente del lago Varese, a causa de las descargas de agua selectivas, no afectó al balance total de nutrientes del lago Maggiore ni a la calidad del agua del río aguas abajo

Epidemiology of Strongyloides stercoralis in northern Italy: Results of a multicentre case-control study, February 2013 to July 2014

Strongyloides stercoralis is a soil-transmitted helminth widely diffused in tropical and subtropical regions of the world. Autochthonous cases have been also diagnosed sporadically in areas of temperate climate. We aimed at defining the epidemiology of strongyloidiasis in immigrants and Italians living in three northern Italian Regions. Screening for S. stercoralis infection was done with serology, confirmation tests were a second serological method or stool agar culture. A case-control approach was adopted and patients with a peripheral eosinophil count 65 500/mcL were classified as cases. Of 2,701 individuals enrolled here 1,351 were cases and 1,350 controls; 86% were Italians, 48% women. Italians testing positive were in 8% (97/1,137) cases and 1% (13/1,178) controls (adjusted odds ratio (aOR) 8.2; 95% confidence interval (CI): 4.5-14.8), while positive immigrants were in 17% (36/214) cases and in 2% (3/172) controls (aOR 9.6; 95% CI: 2.9-32.4). Factors associated with a higher risk of infection for all study participants were eosinophilia (p < 0.001) and immigration (p = 0.001). Overall, strongyloidiasis was nine-times more frequent in individuals with eosinophilia than in those with normal eosinophil count

Daylight entanglement-based quantum key distribution with a quantum dot source

Entanglement-based quantum key distribution can enable secure communication in trusted node-free networks and over long distances. Although implementations exist both in fiber and in free space, the latter approach is often considered challenging due to environmental factors. Here, we implement a quantum communication protocol during daytime for the first time using a quantum dot source. This technology presents advantages in terms of narrower spectral bandwidth-beneficial for filtering out sunlight-and negligible multiphoton emission at peak brightness. We demonstrate continuous operation over the course of three days, across an urban 270 m-long free-space optical link, under different light and weather conditions

Evaluation of pituitary function after infectious meningitis in childhood

Background: A number of studies of adults have shown that pituitary deficiencies can develop in a considerable proportion of subjects during the acute phase of meningitis or years after the infection has disappeared. The results of the very few studies of the impact of pediatric meningitis on hypothalamic-pituitary function are conflicting.Methods: In order to determine the incidence of pituitary dysfunction in children with central nervous system infection, we evaluated pituitary function and anthropometric parameters in 19 children with meningitis of different etiologies (15 males; mean age \ub1 standard deviation [SD] at pituitary evaluation, 5.9 \ub1 4.0\ua0years; mean time from the acute event \ub1 SD, 18 \ub1 10\ua0months).Results: All of the subjects had a normal stature and growth velocity for their age and gender, and none of them was obese. On the basis of Tanner's reference charts, 17 subjects (13 boys and all four girls) were pre-pubertal; two boys were in Tanner stage 2. None of the subjects had central hypothyroidism. All of the patients had normal serum of insulin growth factor (IGF)-I and prolactin. Their sex steroid and gonadotropin levels were concordant with their age and pubertal status. Early morning urine osmolality and serum electrolyte levels showed no signs of diabetes insipidus. All of the patients had normal plasma adrenocorticotropic hormone (ACTH) levels. Peak cortisol responses to the standard dose Synacthen test (SDST) were normal in all cases.Conclusions: The results showed that hypopituitarism following infectious meningitis appears to be infrequent in childhood and children's pituitary glands seem to be less vulnerable to damage than those of adults

Thai visitors’ expectations and experiences of explainer interaction within a science museum context

© The Author(s) 2015. In Western literature, there is evidence that museum explainers offer significant potential for enhancing visitors’ learning through influencing their knowledge, content, action, behaviour and attitudes. However, little research has focused on the role of explainers in other cultural contexts. This study explored interactions between visitors and museum explainers within the setting of Thailand. Two questionnaires were distributed to 600 visitors and 41 museum explainers. The results demonstrated both potential similarities and differences with Western contexts. Explainers appeared to prefer didactic approaches, focussing on factual knowledge rather than encouraging deep learning. Two-way communication, however, appeared to be enhanced by the use of a ‘pseudo-sibling relationship’ by explainers. Traditional Thai social reserve was reduced through such approaches, with visitors taking on active learning roles. These findings have implications for training museum explainers in non-Western cultures, as well as museum communication practice more generally

Repression of Human T-lymphotropic virus type 1 Long Terminal Repeat sense transcription by Sp1 recruitment to novel Sp1 binding sites

Human T-lymphotropic Virus type 1 (HTLV-1) infection is characterized by viral latency in the majority of infected cells and by the absence of viremia. These features are thought to be due to the repression of viral sense transcription in vivo. Here, our in silico analysis of the HTLV-1 Long Terminal Repeat (LTR) promoter nucleotide sequence revealed, in addition to the four Sp1 binding sites previously identified, the presence of two additional potential Sp1 sites within the R region. We demonstrated that the Sp1 and Sp3 transcription factors bound in vitro to these two sites and compared the binding affinity for Sp1 of all six different HTLV-1 Sp1 sites. By chromatin immunoprecipitation experiments, we showed Sp1 recruitment in vivo to the newly identified Sp1 sites. We demonstrated in the nucleosomal context of an episomal reporter vector that the Sp1 sites interfered with both the sense and antisense LTR promoter activities. Interestingly, the Sp1 sites exhibited together a repressor effect on the LTR sense transcriptional activity but had no effect on the LTR antisense activity. Thus, our results demonstrate the presence of two new functional Sp1 binding sites in the HTLV-1 LTR, which act as negative cis-regulatory elements of sense viral transcription.info:eu-repo/semantics/publishe

Final height in growth hormone-deficient childhood cancer survivors after growth hormone therapy

Purpose: Growth hormone deficiency (GHD) is the most prevalent hypothalamic\u2013pituitary (HP) disorder found in childhood cancer survivors (CCS). The published studies assessing GHD in CCS concluded that recombinant human GH (rhGH) does not restore final height (FH) to that predicted from mid-parental height (MPH). Thus, wider analyses on final height outcomes after rhGH in CCS are needed. Methods: Retrospective study on final height (FH) in 87 CCS treated with rhGH. Patients were divided into: Group A (n =48) who underwent cranial radiotherapy or had non-irradiated tumours of HP area, and B (n =39) who were treated with craniospinal or total body irradiation (TBI). 19/87 patients with central precocious/early puberty also received GnRH analogues. Results: Height (HT) gain after 1 and 2 years of rhGH was 0.38 \ub1 0.35 SDS and 0.18 \ub1 0.30 SDS, respectively (P < 0.0001); mean FH was in the normal range ( 12 0.85 \ub1 1.34 SDS), though not significantly different from HT SDS at baseline. 67% overall failed to reach MPH especially in Group B (P < 0.0001). However, height loss (HT SDS-MPH SDS) at FH improved or remained stable compared to baseline in 26/45 patients (58%). On stepwise regression analysis, major determinants of FH were HT at baseline (P < 0.0001) and delay before start of rhGH (P = 0.012). There was no significant difference in FH when GnRHa was added to rhGH. Conclusion: rhGH and GnRH analogues therapy, when indicated, though failing to induce catch-up growth, prevented further height loss leading to a FH within the normal range but still below MPH, this latter being statistically significant in children who received craniospinal and TBI