Underreamer mechanics

In the oil and gas industry, an underreamer is a tool used to extend and enlarge the diameter of a previously-drilled bore. The problem proposed to the Study Group is to obtain appropriate mathematical models of underreamer dynamics, in forms that will lead to feasible computation. The modes of dynamics of interest are torsional, lateral and axial. This report describes some initial models, two of which are developed in more detail: one for the propagation of torsional waves along the drill string and their reflection from contact points with the well bore; and one for the dynamic coupling between the underreamer and the drill bit during drilling

Wiesenkäuterbeimischung in Kleegras - Effekt von Saatmischung und Nutzungshäufigkeit auf Ertrag und Zuwachsdynamik von Kleegras

Legumes and herbs are able to contribute to productivity and biodiversity in forage production. Furthermore they are known for their beneficial properties for animal nutrition and health. In the present study a grass/clover containing herbs and birdsfoot trefoil was compared to a site specific grass/clover with respect to growth dynamics, potential yield and forage quality under varied harvest frequencies. Independent of harvest frequency both seed mixtures achieved comparable yields. Increased harvest frequency led to higher forage quality but reduced dry matter yield. The introduction of herbs and birdsfoot trefoil led to minor decreases in the contents of crude protein and net-energy. When utilised every third or fourth week both seed mixtures were able to supply high lactating dairy cows with high quality forage

Quantifying gliding forces of filamentous cyanobacteria

Filamentous cyanobacteria are one of the oldest and today still most abundant lifeforms on earth, with manifold implications in ecology and economics. Their flexible filaments, often several hundred cells long, exhibit gliding motility in contact with solid surfaces. The underlying force generating mechanism is not yet understood. Here, we demonstrate that propulsion forces and friction coefficients are strongly coupled in the gliding motility of filamentous cyanobacteria. We directly measure their bending moduli using micropipette force sensors, and quantify propulsion and friction forces by analyzing their self-buckling behavior, complemented with analytical theory and simulations. The results indicate that slime extrusion unlikely generates the gliding forces, but support adhesion-based hypotheses, similar to the better-studied single-celled myxobacteria. The critical self-buckling lengths align well with the peaks of natural length distributions, indicating the importance of self-buckling for the organization of their collective in natural and artificial settings.Comment: 13 pages, 4 main figures, 6 supplementary figure

Fighting Antimicrobial Resistance:Development and Implementation of the Ghanaian National Action Plan (2017-2021)

In recent years, Ghana has been recognised as a leading player in addressing antimicrobial resistance (AMR) in Africa. However, based on our literature review, we could not ascertain whether the core elements of the national action plan (NAP) were implemented in practice. In this paper, we present a qualitative analysis of the development of AMR-related policies in Ghana, including the NAP. We conducted 13 semi-structured expert interviews to obtain at a more thorough understanding of the implementation process for the AMR NAP and to highlight its accomplishments and shortcomings. The results show that AMR policies, as embodied in the NAP, have led to an extended network of cooperation between stakeholders in many political fields. Broadly, limited allocation of financial resources from the government and from international cooperation have been deplored. Furthermore, the opportunity for using the NAP in mainstreaming the response to the threat of AMR has not been seized. To the general public, this remained hidden behind a number of other relevant health topics such as infection prevention, veterinary services and pharmaceutical regulation. As a One Health (OH) challenge, developing countries could integrate AMR NAPs into other health and environmental programmes to improve its implementation in practice

Laboratory-based surveillance of antimicrobial resistance in regions of Kenya:An assessment of capacities, practices, and barriers by means of multi-facility survey

BACKGROUND: Adequate laboratory capacity is critical in the implementation of coherent surveillance for antimicrobial resistance (AMR). We describe capacities and deficiencies in laboratory infrastructure and AMR surveillance practices among health facilities in Kenya to support progress toward broader sustainable laboratory-based AMR surveillance. METHODS: A convenience sample of health facilities from both public and private sectors across the country were selected. Information was obtained cross-sectionally between 5th October and 8th December 2020 through online surveys of laboratory managers. The assessment covered quality assurance, management and dissemination of AMR data, material and equipment, staffing, microbiology competency, biosafety and certification. A scoring scheme was developed for the evaluation and interpreted as (80% and above) facility is adequate (60–79%) requires some strengthening and (<60%) needing significant strengthening. Average scores were compared across facilities in public and private sectors, rural and urban settings, as well as national, county, and community levels. RESULTS: Among the participating facilities (n = 219), the majority (n = 135, 61.6%) did not offer bacterial culture testing, 47 (21.5%) offered culture services only and 37 (16.9%) performed antimicrobial susceptibility testing (AST). The major gaps identified among AST facilities were poor access to laboratory information management technology (LIMT) (score: 45.9%) and low uptake of external quality assessment (EQA) programs for cultures (score 67.7%). Access to laboratory technology was more than two-fold higher in facilities in urban (58.6%) relative to rural (25.0%) areas. Whilst laboratories that lacked culture services were found to have significant infrastructural gaps (average score 59.4%), facilities that performed cultures only (average score: 83.6%) and AST (average score: 82.9%) recorded significantly high scores that were very similar across areas assessed. Lack of equipment was identified as the leading challenge to the implementation of susceptibility testing among 46.8% of laboratories. CONCLUSIONS: We identified key gaps in laboratory information management technology, external quality assurance and material and equipment among the surveyed health facilities in Kenya. Our findings suggest that by investing in equipment, facilities performing cultures can be successfully upgraded to provide additional antimicrobial susceptibility testing, presenting a chance for a major leap toward improved AMR diagnostics and surveillance in the country

The underestimated fraction: diversity, challenges and novel insights into unicellular cyanobionts of lichens

Lichens are remarkable and classic examples of symbiotic organisms that have fascinated scientists for centuries. Yet, it has only been for a couple of decades that significant advances have focused on the diversity of their green algal and/or cyanobacterial photobionts. Cyanolichens, which contain cyanobacteria as their photosynthetic partner, include up to 10% of all known lichens and, as such, studies on their cyanobionts are much rarer compared to their green algal counterparts. For the unicellular cyanobionts, i.e. cyanobacteria that do not form filaments, these studies are even scarcer. Nonetheless, these currently include at least 10 different genera in the cosmopolitan lichen order Lichinales. An international consortium (International Network of CyanoBionts; INCb) will tackle this lack of knowledge. In this article, we discuss the status of current unicellular cyanobiont research, compare the taxonomic resolution of photobionts from cyanolichens with those of green algal lichens (chlorolichens), and give a roadmap of research on how to recondition the underestimated fraction of symbiotic unicellular cyanobacteria in lichens

Validation of a proxy‐reported SARC‐F questionnaire for current and retrospective screening of sarcopenia‐related functional impairments

BACKGROUND: The strength, assistance walking, rise from a chair, climb stairs, and falls (SARC‐F) questionnaire is a well‐established instrument for screening of sarcopenia and sarcopenia‐related functional impairments. As it is based on self‐reporting, its use precludes patients who are unable to answer the questionnaire as a consequence of severe acute diseases or cognitive impairment. Therefore, we aimed to validate a proxy‐reported version of the SARC‐F for both ad‐hoc as well as retrospective screening for severe sarcopenia‐related functional impairments. METHODS: Patients aged ≥60 years completed the SARC‐F and performed the short physical performance battery (SPPB) at baseline (T1). Proxies in Cohort A gave a simultaneous assessment of the patients' functional status with the proxy‐reported SARC‐F at T1 and again, retrospectively, after 3 months (T2). Proxies in Cohort B only completed the SARC‐F retrospectively at T2. The questionnaires' performances were assessed through sensitivity/specificity analyses and receiver operating characteristic (ROC) curves. For non‐inferiority analyses, results of both the patient‐reported and proxy‐reported SARC‐F were correlated with the SPPB total score as well as the results of the chair‐rise test subcategory; the respective correlation coefficients were tested against each other. RESULTS: One hundred and four patients and 135 proxies participated. Using a SPPB score < 9 points as the reference standard, the proxy‐reported SARC‐F identified patients at high risk for sarcopenia‐related functional impairment with a sensitivity of 0.81 (ad‐hoc), 0.88 (retrospective Cohort A), and 0.87 (retrospective Cohort B) as well as a specificity of 0.89 (ad‐hoc), 0.78 (retrospective Cohort A), and 0.64 (retrospective Cohort B). Areas under the ROC curves were ≥ 0.9 for the ad‐hoc proxy‐reported SARC‐F and the retrospective proxy‐reported SARC‐F in both cohorts. The proxy‐reported SARC‐F showed a non‐inferior correlation with the SPPB compared with the patient‐reported SARC‐F for ad‐hoc (P = <0.001) as well as retrospective screening for severe sarcopenia‐related functional impairment in both Cohorts A (P = 0.007) and B (P = 0.026). CONCLUSIONS: Proxy‐reported SARC‐F is a valid instrument for both ad‐hoc as well as retrospective screening for sarcopenia‐related functional impairment and could become the standard tool for evaluating this risk in older adults with severe acute disease, for example, in patients with quickly evolving haematological conditions

Regional Variation of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Enterobacterales, Fluoroquinolone-ResistantSalmonella entericaand Methicillin-ResistantStaphylococcus aureusAmong Febrile Patients in Sub-Saharan Africa

Background: Antimicrobial resistance (AMR) thwarts the curative power of drugs and is a present-time global problem. We present data on antimicrobial susceptibility and resistance determinants of bacteria the WHO has highlighted as being key antimicrobial resistance concerns in Africa, to strengthen knowledge of AMR patterns in the region. Methods: Blood, stool, and urine specimens of febrile patients, aged between ≥ 30 days and ≤ 15 years and hospitalized in Burkina Faso, Gabon, Ghana, and Tanzania were cultured from November 2013 to March 2017 (Patients > 15 years were included in Tanzania). Antimicrobial susceptibility testing was performed for all Enterobacterales and Staphylococcus aureus isolates using disk diffusion method. Extended-spectrum beta-lactamase (ESBL) production was confirmed by double-disk diffusion test and the detection of blaCTX–M, blaTEM and blaSHV. Multilocus sequence typing was conducted for ESBL-producing Escherichia coli and Klebsiella pneumoniae, ciprofloxacin-resistant Salmonella enterica and S. aureus. Ciprofloxacin-resistant Salmonella enterica were screened for plasmid-mediated resistance genes and mutations in gyrA, gyrB, parC, and parE. S. aureus isolates were tested for the presence of mecA and Panton-Valentine Leukocidin (PVL) and further genotyped by spa typing. Results: Among 4,052 specimens from 3,012 patients, 219 cultures were positive of which 88.1% (n = 193) were Enterobacterales and 7.3% (n = 16) S. aureus. The prevalence of ESBL-producing Enterobacterales (all CTX-M15 genotype) was 45.2% (14/31; 95% CI: 27.3, 64.0) in Burkina Faso, 25.8% (8/31; 95% CI: 11.9, 44.6) in Gabon, 15.1% (18/119; 95% CI: 9.2, 22.8) in Ghana and 0.0% (0/12; 95% CI: 0.0, 26.5) in Tanzania. ESBL positive non-typhoid Salmonella (n = 3) were detected in Burkina Faso only and methicillin-resistant S. aureus (n = 2) were detected in Ghana only. While sequence type (ST)131 predominated among ESBL E. coli (39.1%;9/23), STs among ESBL K. pneumoniae were highly heterogenous. Ciprofloxacin resistant nt Salmonella were commonest in Burkina Faso (50.0%; 6/12) and all harbored qnrB genes. PVL were found in 81.3% S. aureus. Conclusion: Our findings reveal a distinct susceptibility pattern across the various study regions in Africa, with notably high rates of ESBL-producing Enterobacterales and ciprofloxacin-resistant nt Salmonella in Burkina Faso. This highlights the need for local AMR surveillance and reporting of resistances to support appropriate action

Radiation and Dose-densification of R-CHOP in Primary Mediastinal B-cell Lymphoma: Subgroup Analysis of the UNFOLDER Trial

UNFOLDER (NCT00278408, EUDRACT 2005-005218-19) is a phase-3 trial in patients with aggressive B-cell lymphoma and intermediate prognosis, including primary mediastinal B-cell lymphoma (PMBCL). In a 2 × 2 factorial design, patients were randomized to 6× R-CHOP-14 or R-CHOP-21 (rituximab, cyclophosphamide, doxorubicin, vincristine, and prediso(lo)ne) and to consolidation radiotherapy to extralymphatic/bulky disease or observation. Response was assessed according to the standardized criteria from 1999, which did not include F-18 fluordesoxyglucose positron emission tomography/computed tomography (FDG-PET) scans. Primary end point was event-free survival (EFS). A subgroup of 131 patients with PMBCLs was included (median age, 34 y; 54% female, 79% elevated lactate dehydrogenase (LDH), 20% LDH >2× upper limit of normal [ULN], and 24% extralymphatic involvement). Eighty-two (R-CHOP-21: 43 and R-CHOP-14: 39) patients were assigned to radiotherapy and 49 (R-CHOP-21: 27, R-CHOP-14: 22) to observation. The 3-year EFS was superior in radiotherapy arm (94% [95% confidence interval (CI), 89-99] versus 78% [95% CI, 66-89]; P = 0.0069), due to a lower rate of partial responses (PRs) (2% versus 10%). PR triggered additional treatment, mostly radiotherapy (n = 5; PR: 4; complete response/unconfirmed complete response: 1). No significant differences were observed in progression-free survival (PFS) (95% [95% CI, 90-100] versus 90% [95% CI, 81-98]; P = 0.25) nor in overall survival (OS) (98% [95% CI, 94-100] versus 96% [95% CI, 90-100]; P = 0.64). Comparing R-CHOP-14 and R-CHOP-21, EFS, PFS, and OS were not different. A prognostic marker for adverse outcome was elevated LDH >2× ULN (EFS: P = 0.016; PFS: P = 0.0049; OS: P = 0.0014). With the limitation of a pre-PET-era trial, the results suggest a benefit of radiotherapy only for patients responding to R-CHOP with PR. PMBCL treated with R-CHOP have a favorable prognosis with a 3-year OS of 97%