An extremely low-noise heralded single-photon source: a breakthrough for quantum technologies

Low noise single-photon sources are a critical element for quantum technologies. We present a heralded single-photon source with an extremely low level of residual background photons, by implementing low-jitter detectors and electronics and a fast custom-made pulse generator controlling an optical shutter (a LiNbO3 waveguide optical switch) on the output of the source. This source has a second-order autocorrelation g^{(2)}(0)=0.005(7), and an "Output Noise Factor" (defined as the ratio of the number of noise photons to total photons at the source output channel) of 0.25(1)%. These are the best performance characteristics reported to date

Decapod crustaceans associated with an artificial reef (Adriatic Sea)

The aim of this study is to increase the knowledge on the distribution of decapod crustaceans associated with an artificial reef positioned on sandy-mud bottoms in the central Adriatic Sea. The reef is constituted of concrete modules assembled in pyramids and concrete poles. Hard and soft bottom samples were collected from 2001, just after reef construction, to 2005 (4 surveys per year). Regarding the soft seabed, three sites close to a pyramid, three inside the reef area at a distance of 10-15 m from the structures, and three 200 m outside the reef (control sites) were randomly sampled during each survey. At the same time, three pyramids (vertical and horizontal walls) and three poles were also investigated. After taxonomical analysis, decapod crustaceans were analysed using abundance and species richness. Sites and years were compared using a balanced, fixed effect, 2-way ANOVA and PERMANOVA. In addition, SIMPER analysis was performed to identify those species typifying each community inhabiting both the soft bottom and the artificial substrates. The results showed that the artificial reef induced an increase in both abundance and diversity of the decapods of the natural habitat. In fact, man-made substrates may offer new available space for biological colonization and allow the settlement of new species usually living on hard bottoms, thus increasing the complexity of the original benthic communities

The impact of integrating food supplementation, nutritional education and HAART (Highly Active Antiretroviral Therapy) on the nutritional status of patients living with HIV/AIDS in Mozambique: result from the DREAM programme

DREAM (Drug Resources Enhancement against AIDS and Malnutrition) is a multiregional health program active in Mozambique since 2002 and provides free of charge an integrating package of care consisting of peer to peer nutritional and health education, food supplementation, voluntary counseling and testing, immunological, virological, clinical assessment and HAART (Highly Active AntiRetroviral Treatment). The main goals of this paper are to describe the state of health and nutrition and the adequacy of the diet of a sample of HIV/AIDS patients in Mozambique on HAART and not. A single-arm retrospective cohort study was conducted. 106 HIV/AIDS adult patients (84 in HAART), all receiving food supplementation and peer-to-peer nutritional education, were randomly recruited in Mozambique in two public health centres where DREAM is running. The programme is characterized by: provision of HAART, clinical and laboratory monitoring, peer to peer health and nutritional education and food supplementation. We measured BMI, haemoglobin, viral load, CD4 count at baseline (T0) and after at least 1 year (T1). Dietary intake was estimated using 24h food recall and dietary diversity was assessed by using the Dietary Diversity Score (DDS) at T1. Overall, the patients'diet appeared to be quite balanced in nutrients. In the cohort not in HAART the mean BMI values showed an increases but not significant (initial value: 21.9±2.9; final value: 22.5±3.3 ) and the mean haemoglobin values (g/dl) showed a significant increases (initial value: 10.5+ 2.1; final value: 11.5±1.7 p< 0.024) . In the cohort in HAART, both the mean of BMI value (initial value: 20.7±3.9; final value: 21.9±3.3 p< 0.001) and of haemoglobin (initial value: 9.9±2.2; final value: 10.8±1.7 p< 0.001) showed a higher significant increase. The increase in BMI was statistically associated with the DDS in HAART patients. In conclusion nutritional status improvement was observed in both cohorts. The improvement in BMI was significant and substantially higher in HAART patients because of the impact of HAART on nutritional status of AIDS patients. Subjects on HAART and with a DDS > 5, showed a substantial BMI gain. This association showed an additional expression of the synergic effect of integrating food supplementation, nutritional education and HAART on the nutritional status of African AIDS patients and also highlights the complementary role of an adequate and diversified diet in persons living with HIV/AIDS in resources limited settings

Raja asterias population assessment in FAO GFCM GSA17 area

Population structure and distribution of the starry ray, Raja asterias, were described based on data collected during yearly rapido trawl surveys (SoleMon), between 2005 and 2014 in the Northern and Central Adriatic Sea. A total of 306 individuals were caught, sex ratio was 1.04:1 in favor of males and length-weight relationships were obtained for the whole sample. Following the MEDITS scale, maturity was estimated, observing a higher number of immature individuals. Relative abundance significantly increased during the recent period with the highest values recorded at 5-30 m depths. Such increase could be related to the response of R. asterias to climatic change or to the decrease  in fishing pressure in the area. Clear spatial segregation of individuals depending on their life stage was observed, with immature individuals inhabiting the coastal areas and adults more abundant at depths greater than 40 m. The comparison of the result of the present study with MEDITS survey outcomes in terms of  distribution patterns, persistence areas of adults and juveniles and abundances indices, evidences that SoleMon survey seems to be more suitable in defining such features of the stock, likely due to the greater catchability of the rapido trawl in respect to the MEDITS trawl net. However, further investigations are needed to identify factors affecting the increasing abundance of this species, and develop an action plan for spatial management of fishing activities

Phase modulators ands splitting network on Si PIC coherent fiber beam combining

Coherent beam combining (CBC) of fiber lasers provide an attractive mean of reaching high output laser power by scaling up the available energy while keeping fiber intrinsic advantages of compactness, reliability, efficiency, and beam quality. In CBC architectures, the power of a master oscillator (MO) is divided into N fibers that are amplified individually. The phase perturbations between channels can be measured using various techniques [1-3] and are corrected by individual phase modulators placed on each fiber before the amplification. In this Communication, we present a Silicon PIC integrating a 1:16 channels splitting network and thermal phase modulators array with low electrical power consumption and a bandwidth compatible with CBC requirements. In our CBC system, a 1.55µm CW master oscillator directly feeds the Silicon chip through a grating coupler, as shown in Fig.1(a). The power of the master oscillator is first split on chip into 16 channels, each of which including a thermal phase modulator. The outputs of the 16 waveguides are collectively out-coupled from the chip using a PM optical fiber array aligned and glued onto the PIC’s output grating couplers array [4]. At the other end of fiber array, the 16 fiber outputs are arranged in a 4 by 4 squared lattice, and collimated by a microlens array to form 16 collimated and parallel beamlets. The phase distribution from channel to channel is derived from the fringe pattern resulting from the collimated beamlets interfering with a reference plane wave on a camera. This signal is fed back to drive the PIC’s phase modulators in order to phase lock the 16 fiber

Extended antenatal antiretroviral use correlates with improved infant outcomes throughout the first year of life

OBJECTIVES: To evaluate the effect of extended antenatal triple antiretroviral therapy (ART) on infant outcomes. DESIGN: Retrospective cohort study using pooled data from health clinics in Malawi and Mozambique from July 2005 to December 2009. METHODS: Computerized records of 3273 HIV-infected pregnant women accessing Drug Resource Enhancement Against AIDS and Malnutrition centers were reviewed. ART regimens consisted of nevirapine-based HAART as of 14-25 weeks gestation until 6 months postpartum. Infant infection was determined at 1, 6 and 12 months of age by branched DNA. RESULTS: A total of 3071 pregnancies resulted in 3148 live births. Lost to follow-up, infant deaths and HIV-1 infection rates at 1 and 12 months were 1.3 and 11.5, 0.8 and 6.7 and 0.8 and 2.0, respectively. Infant HIV-1-free survival at 12 months was 92.5%. Mother-to-child transmission and/or infant deaths correlated with length of maternal antenatal ART by multivariate analysis at 1, 6 and 12 months: 14% in women with more than 30 days of triple antenatal ART and 6.9% in mothers receiving at least 90 days of antenatal ART, P = 0.001. Fifty percent of 54 episodes of transmission occurred in women with higher CD4 cell counts (>350 cells/μl). Infant mortality was 67/1000, lower than background rates (78-100/1000). Growth failure (weight-for-age Z score <-2) was present in 8% of infants around birth, 6% at 6 months, 23% at 12 months (lower than country-specific rates). CONCLUSION: Extended antenatal ART is protective against adverse infant outcomes up to 12 months of age even in children born to mothers with higher CD4 cell counts. PMID: 2088528

Reduction of Maternal Mortality with Highly Active Antiretroviral Therapy in a Large Cohort of HIV-Infected Pregnant Women in Malawi and Mozambique

Background: HIV infection is a major contributor to maternal mortality in resource-limited settings. The Drug Resource Enhancement Against AIDS and Malnutrition Programme has been promoting HAART use during pregnancy and postpartum for Prevention-of-mother-to-child-HIV transmission (PMTCT) irrespective of maternal CD4 cell counts since 2002. Methods: Records for all HIV+ pregnancies followed in Mozambique and Malawi from 6/2002 to 6/2010 were reviewed. The cohort was comprised by pregnancies where women were referred for PMTCT and started HAART during prenatal care (n = 8172, group 1) and pregnancies where women were referred on established HAART (n = 1978, group 2). Results: 10,150 pregnancies were followed. Median (IQR) baseline values were age 26 years (IQR:23-30), CD4 count 392 cells/mm(3) (IQR:258-563), Viral Load log(10) 3.9 (IQR:3.2-4.4), BMI 23.4 (IQR:21.5-25.7), Hemoglobin 10.0 (IQR:9.0-11.0). 101 maternal deaths (0.99%) occurred during pregnancy to 6 weeks postpartum: 87 (1.1%) in group 1 and 14 (0.7%) in group 2. Mortality was 1.3% in women with <than 350 CD4 cells/mm(3) and 0.7% in women with greater than 350 CD4s cells/mm(3) [OR = 1.9 (CL 1.3-2.9) p = 0.001]. Mortality was higher in patients with shorter antenatal HAART: 22/991 (2.2%) if less than 30 days and 79/9159 (0.9%) if 31 days or greater [OR = 2.6 (CL 1.6-4.2) p<0.001]. By multivariate analysis, shorter antenatal HAART (p, 0.001), baseline values for CD4 cell count (p = 0.012), hemoglobin (p = 0.02), and BMI (p<0.001) were associated with mortality. Four years later, survival was 92% for women with shorter antenatal HAART and 98% for women on established therapy prior to pregnancy, p = 0.001. Conclusions: Antiretrovirals for PMTCT purposes have significant impact on maternal mortality as do CD4 counts and nutritional status. In resource-limited settings, PMTCT programs should provide universal HAART to all HIV+ pregnant women given its impact in prevention of maternal death

The DREAM model's effectiveness in health promotion of AIDS patients in Africa

This study evaluates the effectiveness of a holistic model for treating people living with AIDS in Africa; the model aims to improve knowledge about AIDS prevention and care, increase trust in the health centre, impact behaviour, and promote a high level of adherence to HAART. The study took place in the context of the DREAM (Drug Resource Enhancement against AIDS and Malnutrition) programme in Mozambique, designed by the Community of Sant'Egidio to treat HIV patients in Africa. It provides patients with free anti-retroviral drugs, laboratory tests (including viral load), home care and nutritional support. This is a prospective study involving 531 patients over a 12-month period. The patients, predominantly poor and with a low level of education, demonstrated a good level of knowledge about AIDS (more than 90% know how it is transmitted) and trust in the treatment, with a relatively small percentage turning to traditional healers. Overall the patients had a low level of engaging in risky sexual behaviour and a very good level of adherence to HAART (69.5% of the 531 subjects had a pill count higher than 95%). The positive results of the programme's educational initiatives were confirmed with the patients' good clinical results

Connectivity in the Deep: Phylogeography of the Velvet Belly Lanternshark

PublishedThe velvet belly lanternshark, Etmopterus spinax, is a deep-sea bioluminescent squaloid shark, found predominantly in the northeast Atlantic and Mediterranean Sea. It has been exposed to relatively high levels of mortality associated with by-catch in some regions. Its late maturity and low fecundity potentially renders it vulnerable to over-exploitation, although little remains known about processes of connectivity between key habitats/regions. This study utilised DNA sequencing of partial regions of the mitochondrial control region and nuclear ribosomal internal transcribed spacer 2 to investigate population structure and phylogeography of this species across the northeast Atlantic and Mediterranean Basin. Despite the inclusion of samples from the range edges or remote locations, no evidence of significant population structure was detected. An important exception was identified using the control region sequence, with much greater (and statistically significant) levels of genetic differentiation between the Mediterranean and Atlantic. This suggests that the Strait of Gibraltar may represent an important bathymetric barrier, separating regions with very low levels of female dispersal. Bayesian estimation of divergence time also places the separation between the Mediterranean and Atlantic lineages within the last 100,000 years, presumably connected with perturbations during the last Glacial Period. These results demonstrate population subdivision at a much smaller geographic distance than has generally been identified in previous work on deep-sea sharks. This highlights a very significant role for shallow bathymetry in promoting genetic differentiation in deepwater taxa. It acts as an important exception to a general paradigm of marine species being connected by high levels of gene-flow, representing single stocks over large scales. It may also have significant implications for the fisheries management of this species.We would like to thank Trude Thangstad, Merete Kvalsund (Institute of Marine Research, Norway), Cecilia Pinto, Eleonora de Sabata and the scientists and crew of the RV Celtic Explorer for assistance in the collection of samples. Funding for this project was provided by the University of Salford and the University of Bristol. We are grateful to all those who helped with sample collection, including the MEDITS survey programme, the Department of Fisheries and Marine Research (DFMR) of Cyprus, the Annual Demersal and Deep Water Fish Monitoring Surveys financed by the Azores Government and the CONDOR project (supported by a grant from Iceland, Liechtenstein, Norway through the EEA Financial Mechanism (PT0040/2008)