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A critical challenge during volcanic emergencies is responding to rapid changes in eruptive behaviour. Actionable advice, essential in times of rising uncertainty, demands the rapid synthesis and communication of multiple datasets with prognoses. The 2020-2021 eruption of La Soufrière volcano exemplifies these challenges: a series of explosions from 9-22 April 2021 was preceded by three months of effusive activity, which commenced with a remarkably low level of detected unrest. Here we show how the development of an evolving conceptual model, and the expression of uncertainties via both elicitation and scenarios associated with this model, were key to anticipating this transition. This not only required input from multiple monitoring datasets but contextualisation via state-of-the-art hazard assessments, and evidence-based knowledge of critical decision-making timescales and community needs. In addition, we share strategies employed as a consequence of constraints on recognising and responding to eruptive transitions in a resource-constrained setting, which may guide similarly challenged volcano observatories worldwide.

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Periventricular leukomalacia (PVL), the principal form of brain injury in the premature infant, is characterized by overt focal necrotic lesions in periventricular white matter and less prominent, more diffuse cerebral white matter injury. The early detection of the latter, diffuse component of PVL is not consistently possible with conventional brain imaging techniques. We demonstrate the early detection of the diffuse component of PVL by diffusion-weighted magnetic resonance imaging (DWI). In a premature infant with no definite cerebral abnormality detectable by cranial ultrasonography or conventional magnetic resonance imaging, DWI showed a striking bilateral decrease in water diffusion in cerebral white matter. The DWI abnormality (ie, decreased apparent diffusion coefficient) was similar to that observed with acute cerebral ischemic lesions in adults. At 10 weeks of age, conventional magnetic resonance imaging and ultrasonography showed striking changes consistent with PVL, including the presence of small cysts. The observations indicate the importance of DWI in the early identification of the diffuse component of PVL and also perhaps the role of ischemia in the pathogenesis of the lesion.

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Dome growth at the Soufriere Hills volcano (1996 to 1998) was frequently accompanied by repetitive cycles of earthquakes, ground deformation, degassing, and explosive eruptions. The cycles reflected unsteady conduit flow of volatile-charged magma resulting from gas exsolution, rheological stiffening, and pressurization. The cycles, over hours to days, initiated when degassed stiff magma retarded flow in the upper conduit. Conduit pressure built with gas exsolution, causing shallow seismicity and edifice inflation. Magma and gas were then expelled and the edifice deflated. The repeat time-scale is controlled by magma ascent rates, degassing, and microlite crystallization kinetics. Cyclic behavior allows short-term forecasting of timing, and of eruption style related to explosivity potential.

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To determine whether exercise intensity influences acute HDL-C responses, 12 male recreational runners (24.8 +/- 4 yr) who ran 15-30 miles.wk-1 exercised on a motor driven treadmill at 60% (L) and 75% (H) VO2max. A counterbalanced experimental design was utilized and energy expenditure was 800 Kcal. Fasting blood samples were obtained 24 h before exercise (24 PRE), immediately post-(IPE), 1 h post- (1 h PE), 6 h post- (6 h PE), and 24 h post- (24 h PE) exercise and analyzed for HDL-C and HDL2&3-C. In addition, postheparin plasma samples, obtained 24 h PRE, 6 h PE, and 24 h PE were analyzed for lipolytic activity--LPLA and HTGLA. An exercise trial by time interaction was observed for HDL-C (P < 0.01). Post-hoc analysis revealed no change in HDL-C following the L trial. However, an increase in HDL-C was observed 24 h PE (P < 0.01) following the H trial. The increase in HDL-C was attributed to an elevated HDL3-C (P < 0.01), with no change in HDL2-C. Analysis of plasma lipolytic activity revealed an increase in LPLA 24 h PE (P < 0.05) which may be responsible for the postexercise alterations in HDL-C. However, HTGLA decreased 6 h PE (P < 0.01) and 24 h PE (P < 0.05). We conclude that increases in HDL-C levels following endurance activity are influenced, in part, by the exercise intensity.

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En julio de 1986 se realizó una encuesta domiciliaria nacional sobre cobertura de vacunación de 3 697 niños ecuatorianos, que brindó la oportunidad de realizar un análisis de costo-eficacia de (1) los servicios de vacunación ordinarios en establecimientos fijos (2) de las campañas de inmunización en masa. Una de las principales finalidades de las campañas fue complementar los servicios de vacunación ordinarios y acelerar las actividades de inmunización. Basándose en la encuesta de la cobertura, el Programa para la Reduccion de la Enfermedad Maternoinfantil (PREMI) y varias campañas anteriores aumentaron la proporción de niños menores de cinco años completamente vacunados de 43 a 64 por ciento. En un año, la campaña del PREMI se encargó de vacunar completamente a 11 por ciento de los niños menores de un año, 21 por ciento de los de 1 a 2 años y 13 por ciento de todos los menores de 5 años. La campaña también ayudó a completar el programa de vacunación cuando los niños eran todavía muy pequeños y estaban expuestos al máximo riesgo. El costo medio por dosis de vacuna (en $US de 1985) fue aproximadamente de $0,29 en los establecimientos fijos y de $0,83 en la campaña del PREMI. El total de los costos nacionales fue de $675 000 y de 1 665 000 en los servicios de vacunación ordinarios y en las campañas, respectivamente. El costo por niño completamente vacunado fue de $44,39 en los primeros y de $8,60 en las últimas. El costo de cada defunción evitada fue de unos $1 900 en los servicios de vacunación ordinarios, de $4 200 en la campaña del PREMI y de $3 200 en el programa combinado. A causa de las menores tasas de mortalidad del Ecuador, los costos por cada defunción evitada en ese país con ambas estrategias no son tan bajos como los observados en estudios pertinentes efectuados en Africa. Las campañas, pese a ser menos eficaces en función del costo que los servicios de vacunación ordinarios, mejoraron significativamente la cobertura de vacunación de los niños menores que no habían sido vacunados en los servicios ordinarios. Al comparar los costos por niño completamente vacunado en ambos servicios con los de programas similares en otros países, los resultados fueron favorables

Disponible en inglés en: Bull. WHO 67(6), 1989

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The present study will examine three common premises in the field of international public health: that the primary care services offered by agencies of the Ministries of Health (MH) are less costly than those offered by Social Security institutions, that the former services are inferior to the latter, and that funds are distributed more equitably by the MH centers among their various recipient populations. The 1986 study compared the costs, quality, and equity of the services in 15 primary care centers in Ecuador--eight Ministry of Health centers and seven rural Social Security (RSS) centers--examining budgetary data from 1985 and obtaining information through a questionnaire and interviews with the personnel at those centers. Average costs were calculated by standardized accounting techniques, and it was confirmed that for several important services, especially medical consultations, these costs were much lower in the Ministry centers than in the Social Security centers. However, no differences in the cost of dental care were detected. The evaluation of quality, based on an analysis of the production structure and process, did not yield uniform results. On the one hand, the distribution of personnel and the allocation of funds for drugs and other supplies indicated that the RSS agencies provided better quality services. On the other hand, a questionnaire revealed that the MH health workers' knowledge of various principles of primary care was superior to that of the RSS workers. Upon comparing the per capita budget of the two types of entities, it was confirmed that the Ministry of Health had more equitable per capita coverage than rural Social Security. The implications of these findings for Ecuador and other developing countries are discussed and several recommendations made.

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To characterize pancreatic endocrine secretion and to examine interrelationships among alterations in alpha, beta, and pancreatic polypeptide cell function in patients with cystic fibrosis (CF), we studied 19 patients with exocrine insufficiency (EXO), including 9 receiving insulin therapy (EXO-IT); 10 patients with no exocrine insufficiency (NEXO); and 10 normal control subjects. First-phase C-peptide response to intravenously administered glucose was significantly impaired in CF patients with exocrine insufficiency (EXO-IT = 0.02 +/- 0.01; EXO = 0.11 +/- 0.02; NEXO = 0.25 +/- 0.05; control subjects = 0.30 +/- 0.04 nmol/L). Lowering fasting glucose levels with exogenous insulin administration in EXO-IT did not improve beta cell responsivity to glucose. The C-peptide response to arginine was less impaired (EXO-IT = 0.12 +/- 0.02; EXO = 0.15 +/- 0.02; NEXO = 0.23 +/- 0.06; control subjects = 0.28 +/- 0.04 nmol/L). Alpha cell function, measured as peak glucagon secretion in response to hypoglycemia, was diminished in EXO but not NEXO (EXO-IT = 21 +/- 10; EXO = 62 +/- 19; NEXO = 123 +/- 29; control subjects = 109 +/- 12 ng/L). Despite diminished glucagon response, EXO patients recovered normally from hypoglycemia. Peak pancreatic polypeptide response to hypoglycemia distinguished CF patients with exocrine insufficiency from those without exocrine insufficiency (EXO-IT = 3 +/- 2; EXO = 3 +/- 1; NEXO = 226 +/- 68; control subjects = 273 +/- 100 pmol/L). Thus CF patients with exocrine disease have less alpha, beta, and pancreatic polypeptide cell function than CF patients without exocrine disease. These data suggest either that exocrine disease causes endocrine dysfunction in CF or that a common pathogenic process simultaneously and independently impairs exocrine and endocrine function.

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This study of costs, quality and financial equity of primary health services in Ecuador, based on 1985 data, examines three assumptions, common in international health, concerning Ministry of Health (MOH) and Social Security (SS) programs. The assumptions are that MOH services are less costly than SS services, that they are of lower quality than SS services, and that MOH programs are more equitable in terms of the distribution of funds available for PHC among different population groups. Full costs of a range of primary health services were estimated by standard accounting techniques for 15 typical health care establishments, 8 operated by the MOH and 7 by the rural SS program (RSSP), serving rural and peri-urban populations in the two major geographical regions of Ecuador. Consistent with the conventional premise, MOH average costs were much lower than RSSP costs for several important types of services, especially those provided by physicians. Little difference was found for dental care. The lower MOH physician service costs appeared to be attributable primarily to lower personnel compensation (only partially offset by lesser productivity) and to greater economies of scope. Several measures of the quality of care were applied, with varying results. Based on staff differences and patterns of expenditures on resource inputs, notably drugs, RSSP quality appeared higher, as assumed. However, contrary to expectation, a questionnaire assessment of staff knowledge and procedures favored the MOH for quality. Program equity was judged in terms of per capita budgeted expenditures (additional measures, such as the likelihood of receiving necessary care, would have required household survey data beyond the scope of this program-based study). The results support the assumption of greater MOH financial equity, as its program reveals less variation in budgeted expenditures between different population groups covered. Additional evidence of equity, using other indicators, would be helpful in future research. The paper's findings have policy implications not only for Ecuador's health sector but also for policy-makers in other countries at similar levels of socioeconomic development. These implications are spelled out in order to guide officials wrestling with issues of efficiency, quality, and equity as they search for the best use of scarce resources to promote health.

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The effect of blood glucose extraction on the perception of exertion was examined during prolonged arm exercise. Eight male subjects consumed in counter-balanced order a standard daily diet containing either (1) 75 g dihydroxyacetone and 25 g sodium pyruvate (DHAP) or (2) an isocaloric amount of placebo, to manipulate blood glucose extraction. Following each 7-day diet, subjects exercised to exhaustion at 60% of peak arm oxygen consumption. Ratings of perceived exertion (Borg, CR-10 scale) were obtained for the arms (RPE-A), legs (RPE-L), chest (RPE-C) and overall body (RPE-O) every 10 min of exercise. After 60 min of continuous exercise, blood samples were drawn from the radial artery and axillary vein. Ratings of perceived exertion did not differ between trials during the first 50 min of exercise. At the 60-min time point, perceived exertion was lower (P less than 0.01) in the DHAP than placebo trials for the arms (RPE-A: 4.25 vs 5.50) and overall body (RPE-O: 3.25 vs 4.00). These differences persisted throughout exercise. RPE-L and RPE-C did not differ between trials. Whole-arm arterial-venous glucose difference was higher (P less than 0.05) in the DHAP (1.00 mmol.l-1) than placebo (0.36 mmol.l-1) trials, as was fractional extraction of glucose (22.5 vs 9.0%). Respiratory exchange ratio was the same between trials. Triceps muscle glycogen was (1) higher in the DHAP than placebo trial at pre-exercise (P less than 0.05), (2) decreased during exercise and (3) did not differ between trials at exercise termination.(ABSTRACT TRUNCATED AT 250 WORDS)

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Isokinetic strength testing has been widely used to assess athletic populations. The purpose of this study was to measure isokinetic strength in nonathletic able-bodied subjects to provide a subsequent comparison with nonathletic injured patients. Using a standard isokinetic protocol, with continuous verbal encouragement, a single investigator tested 16 women and nine men aged 20 to 30 years on an isokinetic dynamometer. Subjects had minimal athletic experience, and none were varsity performers. Peak torque as a percentage of body weight was statistically greater for men than for women in most joints tested both at 60 degrees and 180 degrees per second. The ratio of the last five to the first five of 25 repetitions at 180 degrees/second (Endurance Ratio = ER) rarely (ie, 5/154 tests) fell below the commonly accepted value of 50%. Many subjects had an endurance ratio of 100% or greater (range 4% to 171%). Peak torques were well below and endurance ratios well above those published for similarly aged athletes. The results suggest that before isokinetic testing is considered as a possible way to distinguish malingerers among injured patients, normal values in an age-matched, nonathletic, working population should be clearly defined. The endurance ratio may reflect the level of athletic training or the level of vigorous participation in an exercise program.

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A national household coverage survey of 3697 Ecuadorean children, carried out in July 1986, provided an opportunity for a cost-effectiveness analysis of (1) routine vaccination services based in fixed facilities and (2) mass immunization campaigns. A major purpose of the campaigns was to complement the routine services and to accelerate immunization activities. Based on the coverage survey, the Program for Reduction of Maternal and Childhood Illness (PREMI) and earlier campaigns increased the proportion of children under 5 years who were fully vaccinated from 43% to 64%. In one year, the PREMI campaign was responsible for fully vaccinating 11% of children under one year, 21% of 1-2-year-old children, and 13% of all children under 5 years. The campaign also helped ensure that vaccinations were completed when children were still very young and at greatest risk. The average cost per vaccination dose (in 1985 US$ prices) was approximately $0.29 for fixed facilities and $0.83 for the PREMI campaign. Total national costs were $675,000 and $1,665,000 for routine and campaign services respectively. The cost per fully vaccinated child (FVC) was $4.39 for routine vaccination services and $8.60 for the campaign. The cost per death averted was about $1900 for routine vaccination services, $4200 for the PREMI campaign, and $3200 for the combined programme. Because of Ecuador's lower mortality rates, the costs per death averted in Ecuador from both vaccination strategies are not as low as those from studies of vaccinations in Africa. The campaigns, though less cost-effective than routine services, significantly improved the vaccination coverage of younger children who had been missed by the routine services. The costs per FVC of both the campaign and the routine services compare favourably with such programmes in other countries.

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