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Context. Spacecrafts with imaging telescopes often carry a charge-coupled device (CCD) in their focal plane to detect electromagnetic radiation. Charged particles such as electrons, protons, and heavy ions can reach the CCD and deposit their energy in the detector material. To counteract this undesirable effect, algorithms are usually implemented to reject them. On the other hand, CCDs can also be seen as particle detectors. Aims. Even though rejection algorithms are often active to immediately discard undesired radiation, data including charged particles of ESA's XMM-Newton and Gaia were stored over the whole mission lifetime. In this article we primarily analyse and characterise the charged particles that were detected by XMM-Newton. A comparison to data from Gaia's CCDs is also presented. Methods. To characterise the particle flux in the spacecraft orbits we used all publicly available observations where no rejection algorithm was used in combination with observations where the rejection algorithm was used. The particle flux is analysed over time and space of the XMM-Newton orbit. Comparisons to external data are shown as well. Results. Our analysis shows that the rate of charged particle events has a modulation of about 11 yr and that particle flux and solar activity are anti-correlated. Moreover, we also show that often more than one charged particle hits the CCD simultaneously. Conclusions. Rejection algorithms are typically used to remove charged particle detection and preserve the scientific data missions. In this article, using XMM-Newton and Gaia data, we show that by neglecting rejection algorithms, charged particles detected on CCDs can be analysed and characterised over the spacecraft orbit.

East Africa is among the most environmentally diverse regions of the continent, and this diversity is reflected in its hydrology. The steppe plains, home to much of the region’s great wildlife, are defined by scarcity of rainfall and surface water resources. Within this sea of aridity, mountain peaks such as Kilimanjaro, Kenya, and Meru induce large amounts of rainfall and give rise to rivers that reach out into the grasslands. To the west, the forest–savannah mosaic and the shorelines of the Great Lakes likewise feature plentiful precipitation and surface water, giving rise to abundant vegetation and marine life. The Indian Ocean coast falls between in terms of rain, but its fate has been shaped by oceanic trade. In short, East Africa is a hydrological mosaic that has long influenced the social, cultural, and economic diversity of its human populations. The peoples of East Africa have long depended on the region’s water resources for their livelihoods. They have made sense of the region’s waterscapes, and developed strategies to manage them, in ways that reflected their own needs. Water management consisted not just of hydrological and technological expertise, but also cultural, spiritual, and political expertise. These in turn shaped economic as well as social relationships and hierarchies. With the onset of European colonization in the 19th and 20th centuries, water management became a focal point of struggles between local communities and various colonial actors—government officers, scientists, missionaries, and settlers—who developed very different impressions of the region’s waterscapes. These struggles involved not only conflict over the physical control of water resources, but also debates over what constituted useful and relevant water-management knowledge. Colonial actors described their water management in terms of science and modernity, while existing knowledge and practice were framed as primitive, wasteful, and destructive. Over the 20th century, conflicts intensified as users, African as well as European, demanded larger shares of increasingly scarce water resources. The post-colonial period did not spell an end to these struggles. Since the late 20th century, water management has emerged as a key aspect of national strategies for economic and social development. Yet decades of emphasis and millions of dollars spent have not led to sufficient progress in providing water to everyday people. Today, millions of East Africans lack access to clean, reliable water, a problem that is likely to worsen in the future.

The aim of this quality improvement initiative was to improve the neonatal intensive care unit (NICU) admission rectal temperatures of premature infants less than 28 weeks' gestation by placing them in an occlusive bag from the neck down immediately after birth. The historical control group consisted of a convenience sample of 46 very low-birth-weight infants from March 1, 2010, to August 31, 2010. A convenience sample of 35 very low-birth-weight infants from October 1, 2010, to April 30, 2011, was recruited during the prospective phase. A quasi-experimental design was used. A retrospective medical record review was performed to collect data on NICU admission rectal temperatures for the historical control group. During the prospective phase, infants were placed in a bag from the neck down immediately after birth and NICU admission rectal temperatures were recorded. In both groups, NICU rectal temperatures were measured immediately upon admission. Application of the bag resulted in a higher mean NICU admission rectal temperature in the intervention group compared with the historical control group. Occlusive bags applied at delivery decreased heat loss in premature infants. The results support previous findings and resulted in a change in clinical practice.

The mineralogical and chemical composition of phosphorite concentrates from Tunisia, Estonia (from the Kabala and Toolse deposits), Uzbekistan (Dzheroi-Sardara) and Kazakhstan (Dzhanatas) as well as their apatite structures were studied before and after mechanical activation in a planetary mill for 5 to 240 min. The specific surface area of these concentrates increased during the first 10–30 min and thereafter decreased. The solubility of phosphorus increased proportionally with the size of the apatite crystallites. The changes in the physical and chemical properties following mechanical activation depend mainly on the mineralogical composition of phosphorite concentrates and on the structural characteristics of the apatite. Mechanical treatment in a planetary mill is more efficient in the case of sedimentary phosphorites, particularly Estonian phosphorites, and is less effective in the case of igneous phosphorites.

In order to elucidate the influence of Ca and Mg carbonates with or without the presence of boron, manganese and copper compounds on the thermal stability of ammonium nitrate (AN), thermodynamic analysis of different reactions between AN and additives was carried out. Temperature dependency of Gibbs free energy changes ∆G T and equilibrium composition of reaction products were calculated for a set of reactions using the HSC software. Main solid compounds that can form in the systems of AN and carbonates, were Ca(NO3)2 and Mg(NO3)2, Ca(OH)2 and Mg(OH)2, CaO2 and MgO2, CaO and MgO, and N-containing gaseous compounds NO, N2O and NO2. As a result of H3BO3, MnO2 and CuSO4 addition, the content of CuO, Cu2O and MnO as solids and SO2, SO3 and HBO as gaseous reaction products reached the same level. Thereby, their equilibrium concentrations did not depend on the carbonate origin of CaCO3, MgCO3 or CaMg(CO3)2. Small amount of CuSO4, H3BO3 or MnO2 additive (0.01–0.05 mol) in the system, practically, did not influence the temperature dependencies of ∆G T of the reactions between AN and CaCO3 or CaMg(CO3)2. The influence of additives taken in the larger amount (0.5 mol) was evident and, depending on the additive and reaction, shifted their proceeding temperatures in either direction by more than 300–400 K.

In 1967, the government of Tanzania announced the Rural Water Supply Programme, an ambitious plan to provide piped water to the Chagga-speaking peoples of Mount Kilimanjaro. One of many development projects conceived during the period of Ujamaa socialism, its proponents claimed that it would fuel economic and social development by providing ‘more and better water’ to the people. This article contends that while projects such as the Rural Water Supply Programme were often couched in the values of Ujamaa, they also were crucial to the nation-building strategy of the majority party, the Tanzania African National Union (TANU). Political leaders, notably President Julius Nyerere, hoped to use water as a means of establishing a national presence inside rural communities in a way that would touch the daily lives of nearly everyone. This presence, in turn, would help to guide rural development, undermine ‘traditional’ forms of authority, and solidify the position of the national party in local affairs. On Kiliman...

The results of investigation of MgO participation in the binding of SO2 with lime-containing materials as sorbents are presented. Experiments of SO2 binding into solid phase using model samples of reactive grade MgO and CaO varying the mole ratio of MgO/CaO from 9:1 to 1:9 were carried out. Besides, dolomite and limestone samples with different MgO/CaO mole ratio (from 1.24 to 0.13) and samples of ashes formed at combustion of Estonian oil shale (containing 35-40% of carbonates) and its semicoke were studied Initial samples, intermediate and final products were subjected to chemical, IR-spectroscopy, X-ray and BET specific surface area analyses. The results of the present study confirmed the active participation of MgO in the binding of SO2 into the solid phase. In addition to CaSO4 the formation of Ca,Mg-double sulphate CaMg3(SO4)4 and β-MgSO4 was observed. The presence of CaMg3(SO4)4 was fixed in a large temperature range 400-900°C and that of β-MgSO4 in between 500-700°C. The optimum temperature range for formation and durability of CaMg3(SO4)4 was 700-800°C.

The thermal reactions in the mixtures of hydroxylapatite or fluorapatite and (NH4)2SO4up to 500°C were studied with the purpose of elaborating the conditions of obtaining calcium–ammonium cyclophosphate that could be used as fertilizer. Thermal analysis with a simultaneous FTIR analysis of the evolved gases as well as the analyses of chemical and phase composition of solid products were performed. The thermal changes in the mixtures could be divided into three steps: (1) decomposition of (NH4)2SO4and reactions of apatite with these products at 250–420°C, (2) calcium ammonium polyphosphate formation at 290–450°C, and (3) reaction of CaSO4with CaNH4P3O9at 320–500°C. Higher concentrations of NH3in the gas phase promote the formation of CaNH4P3O9and increase its stability. Calcination at temperatures above 350°C causes decomposition of CaNH4P3O9with a decrease in the content of water-soluble phosphorus and evolvement of SO2.

Two types of thermal effects, caused by substitutions (Ca2+↔ Na+, ↔ CO3 2-, SO4 2-, OH-↔ F-) in synthetic precipitated apatites as well as by sorption of Cd2+, Zn2+, and Cr3+ ions from the solutions were studied by TG/DTA, XRD and FTIR analysis. The temperatures of exothermic effect at 330-340°C and of decomposition of carbonate and sulfate apatites at 650-950°C were shown to depend on the substitutions in the apatite structure.

The reaction of SO2 with synthetic apatites was studied by TG, XRD and IR analyses at 400-1000°C. Due to an interaction of apatite with SO2, destruction of apatite and formation of CaSO4 and diphosphate up to 750°C takes place. The further calcination leads to the formation of β-Ca3(PO4)2 and a part of the SO2 bound is lost again. The amount of SO2 bound with apatite at calcination depends on the substitution ((F- ↔ OH-, PO43- ↔ CO32-, Ca2+ ↔ Mg2+) in its structure.

This paper illustrates how soil boring data is used to determine the formation break-down pressure for the Green Canyon area of the Gulf of Mexico. Example soil boring data is integrated with deeper well log data to accurately estimate overburden stress. Values for the horizontal to vertical effective stress ratios are confirmed by measuring the actual in situ formation break-down pressure while collecting the soil samples. This study shows that upper marine clays for the Green Canyon Area example have horizontal to vertical effective stress ratios of about 1.0 rather than the extrapolated value of 0.33 often used for sands. The current objective of soil-boring geotechnical studies is to aid in the design of platform foundations. This study recommends that oil-boring geotechnical studies be extended to include obtaining data for designing shallow-gas well control systems.

Gluten intolerance (coeliac disease) is characterised by the development of a small intestinal lesion following exposure to the gliadin fraction after consumption of wheat and related cereals. Cellular immune mechanisms are thought to be responsible for gliadin toxicity, but the toxic sequence/s within gliadin have not been clearly established. A panel of synthetic gliadin peptides was tested using peripheral blood mononuclear cells from coeliac patients and two assays for cell-mediated immunity. Using the indirect leucocyte migration inhibition factor and the macrophage procoagulant activity assays, gliadin peptides which were located in the aminoterminal or the proline-rich domain of the alpha/beta gliadin molecule were coeliac-active. Peptides predicted by T cell algorithms or on the basis of homology to adenovirus Ad12 Elb protein and which were located in the proline-poor gliadin domains were inactive. Protein sequence studies which indicate significant homology in the proline-poor gliadin domains with a number of non-coeliac-toxic seed proteins also supported the hypothesis that the proline-rich domains may be more important in the pathogenesis of coeliac disease.

Dexamethasone is often given to intubated neonates to facilitate successful extubation. To study the effects of dexamethasone on pulmonary function immediately following extubation, we conducted a randomized, blinded, placebo-controlled trial in 51 infants. All infants had been intubated for a minimum of 3 days but no more than 30 days. Mean weight at extubation was 2.41 kg in treated infants, 2.25 kg in control infants. When infants were deemed ready for extubation, dexamethasone 0.5 mg/kg/dose or an equal volume of normal saline was given in three doses 8 hours apart. The final dose was given 1 hour before extubation. Esophageal pressure, air flow integrated to tidal volume (Vt), respiratory rate, and heart rate were measured before extubation, immediately following extubation, and every 20 minutes for 80 minutes. Total pulmonary resistance (RTP), dynamic lung compliance (CL), and minute ventilation (VE) were calculated. Forty-two infants completed the study; 19 infants received dexamethasone and 23 received placebo. There was no difference between the two groups in gestational age, weight at study, or length of intubation. Vt, RTP, VE, and CL were not significantly different between the two groups over time; however, RTP increased over time in the placebo group. Heart rate was significantly lower in the dexamethasone group. We conclude that dexamethasone appears to have limited effect on pulmonary function immediately following extubation in the population studied. Further studies should evaluate the drug effect beginning at least 1 hour after extubation.

To examine the effects of varying inspiratory/expiratory ratio (I/E) on cardiorespiratory function during high-frequency oscillation (HFO), 11 saline-lavaged rabbits were ventilated at I/E = 1:2, 1:1.5, 1.5:1, and 2:1 in a paired comparison to a baseline of I/E = 1:1. HFO was delivered by a SensorMedics model 3100 oscillator at a frequency of 10 Hz. Pressure amplitude and proximal mean airway pressure (PPaw) were held constant as I/E was varied from baseline to the experimental I/E. During each paired observation, Pa, Pa, cardiac output, blood pressure, and distal mean airway pressure (DPaw) were measured. © 1992 Wiley-Liss, Inc. We found that as I/E was increased or decreased from 1:1, no significant changes in Pa, Pa, blood pressure, or cardiac output occurred. We conclude that in this model, varying I/E has no significant effect on oxygenation, ventilation, or cardiovascular function.

To assess the accuracy of a pneumotachometer (PN) for tidal volume (VT) measurements during high-frequency oscillation (HFO), we determined simultaneously VT using a PN and a full body plethysmograph (PL) in 12 rabbits. HFO was delivered with an oscillator at a frequency of 10 Hz, mean airway pressure of 8 cm H2O, and inspiratory time of 50%. Pressure amplitude (delta P) was varied as follows: 40, 60, 80, 20, 100, 40 cm H2O. Finally, in ten rabbits a spacer equal in deadspace (VD) to that of the PN (15 ml) was left in-line for 5 min. Blood gases were obtained before and after the spacer was added. We found that VT-PN correlates well with VT-PL (r = .92), although the difference between VT-PN and VT-PL is greater at large VT. Significant respiratory acidosis developed with the spacer in-line. PN may be used to trend VT during HFO but PN must not be left in-line, as increased VD seriously affects ventilation.