Gated communities as club goods: segregation or social cohesion?

Gated communities are normally presented in highly negative terms, based on the common assumption that they contribute to social segregation. In contrast to received wisdom this paper argues that the theory of club goods can be used to understand gating as a response to both real and perceived issues of crime, vandalism and anti-social behaviour. We suggest that gating can help to foster social cohesion by involving a wide spectrum of communities and income groups to: reduce crime, protect parked vehicles, increase safety and enhance the local environment by preventing unsolicited entry. The paper explores through two case studies, how communities struggling with neighbourhood problems including crime are using gating as a way of improving their environment rather than abandoning poorer areas of the city to find a safer home in more residentially segregated better off neighbourhoods. If housing and planning policy makers are to take seriously a commitment to resident democracy and local participation, such concerns should not be dismissed out of hand as examples of 'isolationism' or 'particularistic consumerist interests'

High-frequency cyclicity in the Mediterranean Messinian evaporites: evidence for solar-lunar climate forcing

The deposition of varved sedimentary sequences is usually controlled by climate conditions. The study of two Late Miocene evaporite successions (one halite and the other gypsum) consisting of annual varves has been carried out to reconstruct the paleoclimatic and paleoenvironmental conditions existing during the acme of the Messinian salinity crisis, ~ 6 Ma, when thick evaporite deposits accumulated on the floor of the Mediterranean basin. Spectral analyses of these varved evaporitic successions reveal significant periodicity peaks at around 3-5, 9, 11-13, 20-27 and 50-100 yr. A comparison with modern precipitation data in the western Mediterranean shows that during the acme of the Messinian salinity crisis the climate was not in a permanent evaporitic stage, but in a dynamic situation where evaporite deposition was controlled by quasi-periodic climate oscillations with similarity to modern analogs including Quasi-Biennial Oscillation, El Ni\~no Southern Oscillation, and decadal to secular lunar- and solar-induced cycles. Particularly we found a significant quasi-decadal oscillation with a prominent 9-year peak that is commonly found also in modern temperature records and is present in the contemporary Atlantic Multidecadal Oscillation (AMO) index and Pacific Decadal Oscillation (PDO) index. These cyclicities are common to both ancient and modern climate records because they can be associated with solar and solar-lunar tidal cycles.Comment: 13 pages, 10 figures, 1 Tabl

Scale variability of atmospheric surface layer fluxes of energy and carbon over a tropical rain forest in southwest Amazonia; 1 diurnal conditions

The aim of this study is to investigate the low-frequency characteristics of diurnal turbulent scalar spectra and cospectra near the Amazonian rain forest during the wet and dry seasons. This is because the available turbulent data are often nonstationary and there is no clear spectral gap to separate data into "mean" and "turbulent" parts. Daubechies-8 orthogonal wavelet is used to scale project turbulent signals in order to provide scale variance and covariance estimations. Based on the characteristics of the scale dependence of the scalar fluxes, some classification criteria of this scale dependence are investigated. The total scalar covariance of each 4-hour data run is partitioned in categories of scale covariance contributions. This permits the study of some statistical characteristics of the scalar turbulent fields in each one of these classes and, thus, to give an insight and a possible explanation of the origin of the variability of the scalar fields close to the Amazonian forest. The results have shown that a two-category classification is the most appropriate to describe the kind of observed fluctuations: "turbulent" and "mesoscale" contributions. The largest contribution of the sensible heat, latent heat, and CO2 covariance contributions occurs in the "turbulent" length scales. Mesoscale eddy motions, however, can contribute up to 30% of the total covariances under weak wind conditions. Analysis of scale correlation coefficient [r(Tvq)] between virtual temperature (Tv) and humidity (q) signals shows that the scale patterns of Tv and q variability are not similar and r(Tvq) <1 for all analyzed scales. Scale humidity skewness calculations are negative during the dry season and positive during the wet season. This suggests that different boundary layer moisture regimes occur during the dry and wet seasons

Measurements of soil respiration and simple models dependent on moisture and temperature for an Amazonian southwest tropical forest

Soil respiration plays a significant role in the carbon cycle of Amazonian tropical forests, although in situ measurements have only been poorly reported and the dependence of soil moisture and soil temperature also weakly understood. This work investigates the temporal variability of soil respiration using field measurements, which also included soil moisture, soil temperature and litterfall, from April 2003 to January 2004, in a southwest Brazilian tropical rainforest near Ji-Paraná, Rondônia. The experimental design deployed five automatic (static, semi-opened) soil chambers connected to an infra-red CO2 gas analyzer. The mean half-hourly soil respiration showed a large scattering from 0.6 to 18.9 µmol CO2 m-2 s-1 and the average was 8.0±3.4 µmol CO2 m-2 s-1. Soil respiration varied seasonally, being lower in the dry season and higher in the wet season, which generally responded positively to the variation of soil moisture and temperature year round. The peak was reached in the dry-to-wet season transition (September), this coincided with increasing sunlight, evapotranspiration and ecosystem productivity. Litterfall processes contributed to meet very favorable conditions for biomass decomposition in early wet season, especially the fresh litter on the forest floor accumulated during the dry season. We attempted to fit three models with the data: the exponential Q10 model, the Reichstein model, and the log-soil moisture model. The models do not contradict the scattering of observations, but poorly explain the variance of the half-hourly data, which is improved when the lag-time days averaging is longer. The observations suggested an optimum range of soil moisture, between 0.11

The deep record of the Messinian salinity crisis: Evidence of a non-desiccated Mediterranean Sea

This research is focused on a complete reexamination of the evaporite facies present in all the cores that cut through the topmost deposits of the Messinian salinity crisis lying below the floor of the Mediterranean Sea (DSDP Legs 13 and 42A, ODP Legs 107 and 161). This review suggests that the uppermost evaporite units in both western and eastern deep Mediterranean basins consist mainly of clastic (gypsrudite, gypsarenite and gypsiltite) and fully subaqueous deposits (laminar gypsum, selenite and cumulate halite) that are partially affected by burial anhydritization and tectonic induced recrystallization. No unequivocal evidence of shallow water or even supratidal (sabkha) deposition is in evidence, suggesting that at the very last phase of the salinity crisis the Mediterranean Sea did not experience desiccation, but that deposition took place under permanent subaqueous conditions

Outcomes and safety of concomitant nevirapine and rifampicin treatment under programme conditions in Malawi.

SETTING: Thyolo District Hospital, rural Malawi. OBJECTIVES: To report on 1) clinical, immunological and virological outcomes and 2) safety among human immunodeficiency virus (HIV) infected patients with tuberculosis (TB) who received concurrent nevirapine (NVP) and rifampicin (RMP) based treatment. DESIGN: Retrospective cohort study. METHODS: Analysis of programme data, June-December 2007. RESULTS: Of a total of 156 HIV-infected TB patients who started NVP-based antiretroviral treatment, 136 (87%) completed TB treatment successfully, 16 (10%) died and 5 (4%) were transferred out. Mean body weight and CD4 gain (adults) were respectively 4.4 kg (95%CI 3.3-5.4) and 140 cells/mm(3) (95%CI 117-162). Seventy-four per cent of patients who completed TB treatment and had a viral load performed (n = 74) had undetectable levels (<50 copies/ml), while 17 (22%) had a viral load of 50-1000 copies/ml. Hepatotoxicity was present in 2 (1.3%) patients at baseline. Two patients developed Grade 2 and one developed Grade 3 alanine transaminase enzyme elevations during TB treatment (incidence rate per 10 years of follow-up 4.2, 95%CI 1.4-13.1). There were no reported deaths linked to hepatotoxicity. CONCLUSIONS: In a rural district in Malawi, concomitant NVP and RMP treatment is associated with good TB treatment outcomes and appears safe. Further follow-up of patients would be useful to ascertain the longer-term effects of this concurrent treatment

The Messinian "Calcare di Base" (Sicily, Italy) revisited

Three different types of carbonate deposits are included within the "Calcare di Base",commonly envisaged to record the Messinian salinity crisis onset: type 1 consists of sulphur-bearinglimestones, representing the biogenic product of bacterial sulphate reduction after original gypsum;type 2 comprises dm-thick laminated dolomitic limestones interbedded with diatomites, sapropels andmarls found at the top the Tripoli Formation; type 3, the most common variety, consists of m-thickbrecciated limestones interbedded with shales and clastic gypsum.Type 3 shows sedimentary features suggesting a clastic origin and deposition from high- to lowdensitygravity flows; thus, these deposits can be regarded as an end-member of a large variety ofevaporite-bearing gravity flow deposits, with a dominant carbonate component.The genetic and stratigraphic characterization of these carbonates has strong implications for a bettercomprehension of Messinian events; the three types of Calcare di Base seem to have formed duringdifferent stages of the Messinian salinity crisis (MSC). Type 2 formed in the first stage (5.96-5.60 Ma),and is the only type that can be regarded as the Lower Gypsum time-equivalent. Type 3 was depositedin the second stage (5.60-5.55 Ma) and its base is associated with a regional-scale hiatus and erosion(Messinian erosional surface). Type 1 formed even later, likely in post-Messinian time, throughdiagenetic processes affecting resedimented gypsum deposited during the second stage of the MSC.It follows that not all the Calcare di Base deposits record the onset of the Messinian salinity crisis, ascommonly thought. Thus, a detailed facies characterization of these carbonate deposits is fundamental for both stratigraphic reconstructions and a better comprehension of Messinian events

Comparative measurements of carbon dioxide fluxes from two nearby towers in a central Amazonian rainforest: the Manaus LBA site

Forests around Manaus have staged the oldest and the longest forest-atmosphere CO2 exchange studies made anywhere in the Amazon. Since July 1999 the exchange of CO2, water, and energy, as well as weather variables, have been measured almost continuously over two forests, 11 km apart, in the Cuieiras reserve near Manaus, Brazil. This paper presents the sites and climatology of the region based upon the new data sets. The landscape consists of plateaus dissected by often waterlogged valleys, and the two sites differ in terms of the relative areas of those two landscape components represented in the tower footprints. The radiation and wind climate was similar to both towers. Generally, both the long-wave and short-wave radiation input was less in the wet than in the dry season. The energy balance closure was imperfect (on average 80%) in both towers, with little variation in energy partitioning between the wet and dry seasons; likely a result of anomalously high rainfall in the 1999 dry season. Fluxes of CO2 also showed little seasonal variation except for a slightly shorter daytime uptake duration and somewhat lower respiratory fluxes in the dry season. The net effect is one of lower daily net ecosystem exchange (NEE) in the dry season. The tower, which has less waterlogged valley areas in its footprint, measured a higher overall CO2 uptake rate. We found that on first sight, NEE is underestimated during calm nights, as was observed in many other tower sites before. However, a closer inspection of the diurnal variation of CO2 storage fluxes and NEE suggests that at least part of the nighttime deficits is recovered from either lateral influx of CO2 from valleys or outgassing of soil storage. Therefore there is a high uncertainty in the magnitude of nocturnal NEE, and consequently preliminary estimates of annual carbon uptake reflecting this range from 1 to 8 T ha-1 y-1, with an even higher upper range for the less waterlogged area. The high uptake rates are clearly unsustainable and call for further investigations into the integral carbon balance of Amazon landscapes

Trocas de energia entre a superfície e atmosfera durante a estação seca no semi-árido nordestino.

O principal objetivo desse estudo é avaliar as trocas turbulentas de energia entre a superfície e a atmosfera acima da Caatinga, e verificar a influência de alguns parâmetros meteorológicos nessas trocas.A Biblioteca possui os resumos em papel

Congenital Rubella Syndrome in Fiji, 1995-2010

Setting. A nationwide study in Fiji. Objective. To describe the incidence of congenital rubella syndrome (CRS) and its relationship to the incidence of notified cases of rubella in Fiji from 1995 to 2010. Design. Descriptive, retrospective review of all recorded congenital abnormalities associated with live births in Fiji over 16 years. Results. There were 294 infants who met the criteria for CRS. Of these, 95% were classified as "suspected" cases, 5% were "clinically confirmed," and none were "laboratory confirmed cases". There was a significant linear increase over the study period in the incidence of CRS (odds ratio 1.045 per year, 95% CI 1.019 to 1.071, P ≤ 0.001). There was no significant association between the incidence of CRS and the reported incidence of rubella (P = 0.3). Conclusion. There is a rising trend in reports of suspected CRS cases in Fiji. This highlights the need to strengthen surveillance for CRS through improvements in clinical and laboratory diagnosis to confirm or exclude suspected cases. It is also important to ensure high coverage of rubella vaccination in Fiji