Extracting gravity wave parameters during the September 2002 Southern Hemisphere major sudden stratospheric warming using a SANAE imaging riometer

Using absorption data measured by imaging riometer for ionospheric studies (IRIS) located at the South Africa National Antarctic Expedition (SANAE), Antarctica (72° S, 3° W), we extracted the parameters of gravity waves (GW) of periods between 40 and 50 min during late winter/spring of the year 2002, a period of the unprecedented major sudden stratospheric warming (SSW) in the Southern Hemisphere middle atmosphere. During this period, an unprecedented substantial increase of temperature by about 25–30 K throughout the stratosphere was observed. During the period of the occurrence of the major stratospheric warming, there was a reduction of both the GW horizontal phase speeds and the horizontal wavelengths at 90 km. The GW phase speeds and horizontal wavelengths were observed to reach minimum values of about 7 m s⁻¹ and 19 km, respectively, while during the quiet period the average value of the phase speed and horizontal wavelength was approximately 23 m s⁻¹ and 62 km, respectively. The observed event is discussed in terms of momentum flux and also a potential interaction of gravity waves, planetary waves and mean circulation

The weak to strong state involvement and political accountability levels schema

The propositionis that socio-economic development from local to national levels often straddles at least four pathways that are driven by two main variables:the relative strength or weakness of (1) state (and government) involvementin the management of public affairs and resources and (2) the mechanisms for ensuring political accountability. The four pathways, with associated attributes, have presented opportunities or challenges that have promoted or collapsed the sustainable economic development of many post-colonial countries. Using the two main variables we can locate different countries in distinct categories (quadrants) across a two-dimensional Cartesianplane, with state involvement on the Y-axis and state and government accountability to citizens on the X-axis

Comparison of total column ozone obtained by the IASI-MetOp satellite with ground-based and OMI satellite observations in the southern tropics and subtropics

International audienceThis paper presents comparison results of the total column ozone (TCO) data product over 13 southern tropical and subtropical sites recorded from the Infrared Atmospheric Sounder Interferometer (IASI) onboard the EU-METSAT (European organization for the exploitation of METeorological SATellite) MetOp (Meteorological Operational satellite program) satellite. TCO monthly averages obtained from IASI between June 2008 and December 2012 are compared with collocated TCO measurements from the Ozone Monitoring Instrument (OMI) on the OMI/Aura satellite and the Dobson and SAOZ (Système d'Analyse par Observation Zénithale) ground-based instruments. The results show that IASI displays a positive bias with an average less than 2 % with respect to OMI and Dobson observations, but exhibits a negative bias compared to SAOZ over Bauru with a bias around 2.63 %. There is a good agreement between IASI and the other instruments, especially from 15 • S southward where a correlation coefficient higher than 0.87 is found. IASI exhibits a seasonal dependence, with an upward trend in autumn and a downward trend during spring, especially before September 2010. After September 2010, the autumn seasonal bias is considerably reduced due to changes made to the retrieval algorithm of the IASI level 2 (L2) product. The L2 product released after August (L2 O 3 version 5 (v5)) matches TCO from the other instruments better compared to version 4 (v4), which was released between June 2008 and August 2010. IASI bias error recorded from September 2010 is estimated to be at 1.5 % with respect to OMI and less than ±1 % with respect to the other ground-based instruments. Thus, the improvement made by O 3 L2 version 5 (v5) product compared with version 4 (v4), allows IASI TCO products to be used with confidence to study the distribution and interannual variability of total ozone in the southern tropics and subtropics. Keywords. Atmospheric composition and structure (middle atmosphere – composition and chemistry

Physical, political and local practice factors as barriers to agricultural development: a case of the Kat River valley, South Africa

The Kat River Valley, in the Eastern Cape of South Africa, provided a case study against which propositions of determinants of economic development were tested. Physical location was found to matter in determining the level of development and economic leverage which Middle Kat farmers had compared to those downstream in accordance with Bromley's (1982) proposition. Physical location, however, was not a determining factor for farmers in the Upper Kat River who were the least developed. As predicted by Ostrom (1990), high transaction costs stemming from information asymmetries, selfish interests coupled with poor leadership, an unequal distribution of power and the flouting of formal agreements ensured the demise of a once successful Hacop project in the Upper Kat. Finally, Hirschman's (1960) much earlier line of argument was supported in that the nature of proposed development programmes and the compatibility with community values or ‘self images’ contributed to the lack of success of an externally initiated development effort. The findings and conclusion serve an important lesson to economic researchers and decision makers not to duplicate policies for implementation in all geographical and social contexts on the basis of their success elsewhere

Comparación de columna total de ozono OMI-DOAS con mediciones terrestres en Argentina

Total ozone column (TOC) measurements through the Ozone Monitoring Instrument (OMI/NASA EOSAura) are compared with ground-based observations made using Dobson and SAOZ instruments for the period 2004–2019 and 2008–02/2020, respectively. The OMI data were inverted using the Differential Optical Absorption Spectroscopy algorithm (overpass OMI-DOAS). The four ground-based sites used for the analysis are located in subpolar and subtropical latitudes spanning from 34°S to 54°S in the Southern Hemisphere, in the Argentine cities of Buenos Aires (34.58°S, 58.36°W; 25 m a.s.l.), Comodoro Rivadavia (45.86°S, 67.50°W; 46 m a.s.l.), Río Gallegos (51.60°S, 69.30°W; 72 m a.s.l.) and Ushuaia (54.80°S, 68.30°W; 14 m a.s.l.). The linear regression analyzes showed correlation values greater than 0.90 for all sites. The OMI measurements revealed an overestimation of less than 4 % with respect to the Dobson instruments, while the comparison with the SAOZ instrument presented a very low underestimation of less than 1 %.En este trabajo se comparan mediciones de columna total de ozono (CTO) del Ozone Monitoring Instrument (OMI/NASA EOS-Aura), con observaciones terrestres de instrumentos Dobson y SAOZ para el periodo 2004–2019 y 2008–02/2020, respectivamente. Los datos del OMI analizados fueron los invertidos mediante el algoritmo Differential Optical Absorption Spectroscopy (overpass OMI-DOAS). Las 4 estaciones terrestres están ubicadas en latitudes subpolares y subtropicales del Hemisferio Sur, en las ciudades argentinas de Buenos Aires (34,58°S, 58,36°O; 25 m s.n.m.), Comodoro Rivadavia (45,86°S, 67,50°O; 46 m s.n.m.), Río Gallegos (51,60°S, 69,30°O; 72 m s.n.m.) y Ushuaia (54,80°S, 68,30°O; 14 m s.n.m.) cubriendo un rango latitudinal desde los 34°S hasta los 54°S. Los análisis de regresión lineal presentan valores de correlación superior a 0,90. Las mediciones OMI– DOAS muestran una sobrestimación menor al 4 % respecto de los instrumentos Dobson, mientras que la comparación respecto al instrumento SAOZ presenta una muy baja subestimación, menor al 1 %.Fil: Orte, Pablo Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; ArgentinaFil: Luccini, Eduardo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Excelencia en Productos y Procesos de Córdoba; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Facultad de Química e Ingeniería-Rosario; ArgentinaFil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Nollas, Fernando Martin. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional. Servicio Metereológico Nacional (sede Dorrego).; ArgentinaFil: Pallotta, Juan Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: D'elia, Raul Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; ArgentinaFil: Carbajal, G.. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional. Servicio Metereológico Nacional (sede Dorrego).; ArgentinaFil: Mbatha, N.. University of Zululand; SudáfricaFil: Hlongwana, N.. University of Zululand; Sudáfric

A cluster‐randomized controlled trial to improve the quality of integrated HIV‐tuberculosis services in primary healthcareclinics in South Africa

Introduction: Tuberculosis (TB) remains the most common cause of death among people living with HIV. Integrating HIV and TB services reduces mortality but is sub-optimally implemented. Quality improvement (QI) methods offer a low-cost and easily implementable approach to strengthening healthcare delivery systems. This trial assessed a QI intervention on key process indicators for delivering integrated HIV-TB care in rural South African primary healthcare (PHC) clinics. Methods: Sixteen nurse supervisors, (each with a cluster of clinics) overseeing 40 PHC clinics, were randomized 1:1 to the intervention or the standard of care (SOC) groups. The QI intervention comprised three key components: clinical and QI skills training, on-site mentorship of nurse supervisors and clinic staff, and data quality improvement activities to enhance accuracy and completeness of routine clinic data. The SOC comprised monthly supervision and data feedback meetings. From 01 December 2016 to 31 December 2018, data were collected monthly by a team of study-appointed data capturers from all study clinics. This study's outcomes were HIV testing services (HTS), TB screening, antiretroviral therapy (ART) initiation, isoniazid preventive therapy (IPT) initiation and viral load (VL) testing. Results: The QI group (eight clusters) comprised 244 clinic staff who attended to 13,347 patients during the trial compared to the SOC group (eight clusters) with 217 clinic staff who attended to 8141 patients. QI mentors completed 85% (510/600) of expected QI mentorship visits to QI clinics. HTS was 19% higher [94.5% vs. 79.6%; relative risk (RR)=1.19; 95% CI: 1.02–1.38; p=0.029] and IPT initiation was 66% higher (61.2 vs. 36.8; RR=1.66; 95% CI: 1.02–2.72; p=0·044), in the QI group compared to SOC group. The percentage of patients screened for TB (83.4% vs. 79.3%; RR=1.05; p=0.448), initiated on ART (91.7 vs. 95.5; RR=0.96; p=0.172) and VL testing (72.2% vs. 72.8%; RR=0.99; p=0.879) was similar in both groups. Conclusions: QI improved HIV testing and IPT initiation compared to SOC. TB screening, ART initiation and VL testing remained similar. Incorporating QI methods into routine supervision and support activities may strengthen integrated HIV-TB service delivery and increase the success of future QI scale-up activities

Programmed Iteration Controls the Assembly of the Nonanoic Acid Side Chain of the Antibiotic Mupirocin

\ua9 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH. Mupirocin is a clinically important antibiotic produced by Pseudomonas fluorescens NCIMB 10586 that is assembled by a complex trans-AT polyketide synthase. The polyketide fragment, monic acid, is esterified by a 9-hydroxynonanoic acid (9HN) side chain which is essential for biological activity. The ester side chain assembly is initialised from a 3-hydroxypropionate (3HP) starter unit attached to the acyl carrier protein (ACP) MacpD, but the fate of this species is unknown. Herein we report the application of NMR spectroscopy, mass spectrometry, chemical probes and in vitro assays to establish the remaining steps of 9HN biosynthesis. These investigations reveal a complex interplay between a novel iterative or “stuttering” KS-AT didomain (MmpF), the multidomain module MmpB and multiple ACPs. This work has important implications for understanding the late-stage biosynthetic steps of mupirocin and will be important for future engineering of related trans-AT biosynthetic pathways (e.g. thiomarinol)

CD8 lymphocytes mitigate HIV-1 persistence in lymph node follicular helper T cells during hyperacute-treated infection

HIV persistence in tissue sites despite ART is a major barrier to HIV cure. Detailed studies of HIV-infected cells and immune responses in native lymph node tissue environment is critical for gaining insight into immune mechanisms impacting HIV persistence and clearance in tissue sanctuary sites. We compared HIV persistence and HIV-specific T cell responses in lymph node biopsies obtained from 14 individuals who initiated therapy in Fiebig stages I/II, 5 persons treated in Fiebig stages III-V and 17 late treated individuals who initiated ART in Fiebig VI and beyond. Using multicolor immunofluorescence staining and in situ hybridization, we detect HIV RNA and/or protein in 12 of 14 Fiebig I/II treated persons on suppressive therapy for 1 to 55 months, and in late treated persons with persistent antigens. CXCR3(+) T follicular helper cells harbor the greatest amounts of gag mRNA transcripts. Notably, HIV-specific CD8(+) T cells responses are associated with lower HIV antigen burden, suggesting that these responses may contribute to HIV suppression in lymph nodes during therapy. These results reveal HIV persistence despite the initiation of ART in hyperacute infection and highlight the contribution of virus-specific responses to HIV suppression in tissue sanctuaries during suppressive ART

Identification of patients with recent-onset psychosis in KwaZulu Natal, South Africa:a pilot study with traditional health practitioners and diagnostic instruments

There is considerable variation in epidemiology and clinical course of psychotic disorders across social and geographical contexts. To date, very little data are available from low- and middle-income countries. In sub-Saharan Africa, most people with psychoses remain undetected and untreated, partly due to lack of formal health care services. This study in rural South Africa aimed to investigate if it is possible to identify individuals with recent-onset psychosis in collaboration with traditional health practitioners (THPs)

South African Children: A Matched Cohort Study of Neurodevelopmental Impairment in Survivors of Invasive Group B Streptococcus Disease Aged 5 to 8 Years.

BACKGROUND: Invasive group B Streptococcus (iGBS) sepsis and meningitis are important causes of child mortality, but studies on neurodevelopmental impairment (NDI) after iGBS are limited. Using Griffiths Mental Development Scales-Extended Revised (GMDS-ER), we described NDI in iGBS survivors and non-iGBS children from South Africa, as part of a 5-country study. METHODS: We identified children aged 5-8 years with a history of iGBS and children with no history of iGBS between October 2019 and January 2021. Children were matched on sex, and birth data (month, year) (matched cohort study). Moderate or Severe NDI was the primary outcome as a composite of GMDS-ER motor, GMDS-ER cognition, hearing, and vision. Secondary outcomes included mild NDI, any emotional-behavioral problems, and GMDS-ER developmental quotients (DQ) calculated by dividing the age equivalent GMDS-ER score by the chronological age. RESULTS: In total, 160 children (iGBS survivors, 43; non-iGBS, 117) were assessed. Among iGBS survivors 13 (30.2%) had meningitis, and 30 (69.8%) had sepsis. Six (13.9%) iGBS survivors, and 5 (4.3%) non-iGBS children had moderate or severe NDI. Children who survived iGBS were 5.56 (95% confidence interval [CI]: 1.07-28.93; P = .041) times more likely to have moderate or severe NDI at 5-8 years than non-iGBS children. Compared to the non-iGBS children, iGBS meningitis survivors had a significantly lower global median DQ (P < .05), as well as a lower median DQ for the language GMDS-ER subscale and performance GMDS-ER subscale (P < .05). CONCLUSIONS: Children surviving iGBS, particularly meningitis, are more likely to have NDI at 5-8 years compared to non-iGBS children. Further research is required to improve detection and care for at-risk newborns