4,633 research outputs found
Healthcare worker\u27s understanding of perinatal depression and maternal mental health service needs in rural Kenya
Background: Perinatal depression is a significant maternal mental health issue in sub-Saharan Africa. Because of the severe shortage of mental health specialists in this region, healthcare workers can be trained to deliver mental health services. Yet, little research has examined their views about maternal mental health. Aims: To help inform the development of a perinatal depression screening program, the aim of this pilot study was to explore the knowledge and understanding of perinatal depression among healthcare workers in rural Kenya. Methods: Fourteen healthcare workers participated in focus group interviews. Results: Content analysis of interview data yielded three primary themes: 1) healthcare workers’ knowledge and understanding of perinatal depression, 2) symptoms of perinatal depression, and 3) identification of perinatal mental health help-seeking resources and barriers in a rural community. Additionally, healthcare workers used a hierarchical approach to manage perinatal depressive symptoms, first by using available resources at the clinic, followed by psychiatric referral as indicated. Conclusions: Healthcare professionals may use study findings to enhance awareness of barriers and stigma associated with perinatal depression and to create a culturally sensitive mental health program for women in this rural community
Assessing sinus aerosol deposition: benefits of SPECT-CT imaging
International audiencePurpose: Aerosol inhalation therapy is one of the methods to treat rhinosinusitis. However the topical drug delivery to the posterior nose and paranasal sinuses shows only limited efficiency. A precise sinusal targeting remains a main challenge for aerosol treatment of sinus disorders. This paper proposes a comparative study of the nasal deposition patterns of micron and submicron particles using planar gamma-scintigraphy imaging vs. a new 3-dimensional (3D) imaging approach based on SPECT-CT measurements. Methods: Radiolabelled nebulizations have been performed on a plastinated model of human nasal cast coupled with a respiratory pump. First, the benefits provided by SPECT-CT imaging were compared with 2D gamma-scintigraphy and radioactive quantification of maxillary sinus lavage as reference for the sonic 2.8 μm aerosol sinusal deposition. Then, the impact on nasal deposition of various airborne particle sizes was assessed. Results: The 2D methodology overestimates aerosol deposition in the maxillary sinuses by a factor 9 whereas the 3D methodology is in agreement with the maxillary sinus lavage reference methodology. Then with the SPECT-CT approach we highlighted that the higher particle size was mainly deposited in the central nasal cavity contrary to the submicron aerosol particles (33.8 ± 0.6% of total deposition for the 2.8 μm particles vs. 1 ± 0.3% for the 230 nm particles). Conclusion: Benefits of SPECT/CT for the assessment of radiolabelled aerosol deposition in rhinology are clearly demonstrated. This 3D methodology should be preferentially used for scintigraphic imaging of sinusal deposition in Human
Elastic energy driven multivariant selection in martensites via quantum annealing
We demonstrate the use of quantum annealing for the selection of multiple
martensite variants in a microstructure with long-range coherency stresses and
external mechanical load. The general approach is illustrated for martensites
with four different variants, based on the minimization of the linear elastic
energy. The equilibrium variant distribution is then analysed under application
of tensile and shear strains and for different values of the considered shear
and tetragonal contributions of the different martensite variants. The
interface orientations between different domains of variants can be explained
using the perspective of the elastic energy anisotropy for regular stripe
patterns. For random grain orientations, the response to an external elastic
strain is weaker and variants changes can be interpreted based on the rotated
eigenstrain tensor
Benefits and limitations of text messages to stimulate higher learning among community providers: participants’ views of an mHealth intervention to support continuing medical education in Vietnam
BACKGROUND: A randomized controlled trial was conducted in 2015 to evaluate a mobile continuing medical education (mCME) intervention that provided daily text messages to community-based physicians’ assistants (CBPAs) in Thai Nguyen Province, Vietnam. Although the intervention failed to improve medical knowledge over a 6-month period, a companion qualitative study provided insights on the views and experiences of intervention participants.
METHODS: We conducted focus group discussions (FGDs) and in-depth interviews (IDIs) among participants randomized to receive text messages containing either simple medical facts or quiz questions. Trained interviewers collected data immediately following the conclusion of the trial in December 2015. Using semi-structured question guides, respondents were queried on their views of the intervention, positive and negative, and perceived impacts of the intervention. During analysis, after learning that the intervention had failed to increase knowledge among participants, we also examined reasons for lack of improvement in medical knowledge. All analyses were performed in NVivo using a thematic approach.
RESULTS: A total of 70 CBPAs engaged in one of 8 FGDs or an IDI. One-half were men; average age among all respondents was 40 years. Most (81%) practiced in rural settings and most (51%) focused on general medicine. The mean length of work experience was 3 years. All respondents made positive comments about the intervention; convenience, relevance, and quick feedback (quiz format) were praised. Downsides encompassed lack of depth of information, weak interaction, technology challenges, and challenging/irrelevant messages. Respondents described perceived impacts encompassing increased motivation, knowledge, collegial discussions, Internet use to search for more information, and clinical skills. Overall, they expressed a desire for the intervention to continue and recommended expansion to other medical professionals. Overreliance on the text messages, lack of effective self-study, and technical/language-based barriers may be potential explanations for intervention failure.
CONCLUSION: As a form of mCME, daily text messages were well-received by community-level health care providers in Vietnam. This mCME approach appears very promising in low-resource environments or where traditional forms of CME are impractical. Future models might consider enhancements to foster linkages to relevant medical materials, improve interaction with medical experts, and tailor medical content to the daily activities of medical staff
Multi-label and multimodal classifier for affectve states recognition in virtual rehabilitation
Computational systems that process multiple affective states may benefit from explicitly considering the interaction between
the states to enhance their recognition performance. This work proposes the combination of a multi-label classifier, Circular Classifier
Chain (CCC), with a multimodal classifier, Fusion using a Semi-Naive Bayesian classifier (FSNBC), to include explicitly the
dependencies between multiple affective states during the automatic recognition process. This combination of classifiers is applied to a
virtual rehabilitation context of post-stroke patients. We collected data from post-stroke patients, which include finger pressure, hand
movements, and facial expressions during ten longitudinal sessions. Videos of the sessions were labelled by clinicians to recognize
four states: tiredness, anxiety, pain, and engagement. Each state was modelled by the FSNBC receiving the information of finger
pressure, hand movements, and facial expressions. The four FSNBCs were linked in the CCC to exploit the dependency relationships
between the states. The convergence of CCC was reached by 5 iterations at most for all the patients. Results (ROC AUC) of CCC with
the FSNBC are over 0.940 ± 0.045 (mean ± std. deviation) for the four states. Relationships of mutual exclusion between engagement
and all the other states and co-occurrences between pain and anxiety were detected and discussed
Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina
In most cases, gauged river flow records in southern South America extend for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering the opportunity of extending the limited hydrological instrumental data to several centuries. In northern Patagonia, Argentina, the Neuquén River has great importance for local and national socio-economic activities such as hydroelectric power generation, agriculture and tourism. In this study, new and updated tree-ring chronologies from Araucaria araucana and Austrocedrus chilensis are used to reconstruct the October-June mean streamflow for the Neuquén River and place the period of gauged flows (1903-2009), in a long-term, multi-century context. The reconstruction covers the period 1346-2000 AD and was developed from a network of 43 tree-ring chronologies, grouped in composite series, using a nested principal component regression approach. Analyses of the frequency, intensity, and duration of droughts and pluvial events indicate that the 20th century contains some of the driest and wettest annual to decadal-scale events in the last 654 yr, but longer and more severe events were recorded in previous centuries. Blackman-Tukey and singular spectral analyses identified quasiperiodic oscillations from 3.5 to 17.5 yr. A dominant 6.8-yr cycle explains ca. 23.6% of the total variance in the Neuquén River streamflow reconstruction. Correlation analyses showed that discharges of the Neuquén River are related to variations in the Southern Annular Mode (SAM), a measure of air mass exchanges between middle and high latitudes in the Southern Hemisphere. This association is consistent with previous studies that indicate a strong correlation between rainfall in northern Patagonia and SAM variations.Facultad de Ciencias Agrarias y Forestale
Low-dimensional controllability of brain networks
Network controllability is a powerful tool to study causal relationships in
complex systems and identify the driver nodes for steering the network dynamics
into desired states. However, due to ill-posed conditions, results become
unreliable when the number of drivers becomes too small compared to the network
size. This is a very common situation, particularly in real-world applications,
where the possibility to access multiple nodes at the same time is limited by
technological constraints, such as in the human brain. Although targeting
smaller network parts might improve accuracy, challenges may remain for
extremely unbalanced situations, when for example there is one single driver.
To address this problem, we developed a mathematical framework that combines
concepts from spectral graph theory and modern network science. Instead of
controlling the original network dynamics, we aimed to control its
low-dimensional embedding into the topological space derived from the network
Laplacian. By performing extensive simulations on synthetic networks, we showed
that a relatively low number of projected components is enough to improve the
overall control accuracy, notably when dealing with very few drivers. Based on
these findings, we introduced alternative low-dimensional controllability
metrics and used them to identify the main driver areas of the human connectome
obtained from N=6134 healthy individuals in the UK-biobank cohort. Results
revealed previously unappreciated influential regions compared to standard
approaches, enabled to draw control maps between distinct specialized
large-scale brain systems, and yielded an anatomically-based understanding of
hemispheric functional lateralization. Taken together, our results offered a
theoretically-grounded solution to deal with network controllability in
real-life applications and provided insights into the causal interactions of
the human brain
Transient peak-strain matching partially recovers the age-impaired mechanoadaptive cortical bone response
Mechanoadaptation maintains bone mass and architecture; its failure underlies age-related decline in bone strength. It is unclear whether this is due to failure of osteocytes to sense strain, osteoblasts to form bone or insufficient mechanical stimulus. Mechanoadaptation can be restored to aged bone by surgical neurectomy, suggesting that changes in loading history can rescue mechanoadaptation. We use non-biased, whole-bone tibial analyses, along with characterisation of surface strains and ensuing mechanoadaptive responses in mice at a range of ages, to explore whether sufficient load magnitude can activate mechanoadaptation in aged bone. We find that younger mice adapt when imposed strains are lower than in mature and aged bone. Intriguingly, imposition of short-term, high magnitude loading effectively primes cortical but not trabecular bone of aged mice to respond. This response was regionally-matched to highest strains measured by digital image correlation and to osteocytic mechanoactivation. These data indicate that aged bone’s loading response can be partially recovered, non-invasively by transient, focal high strain regions. Our results indicate that old murine bone does respond to load when the loading is of sufficient magnitude, and bones’ age-related adaptation failure may be due to insufficient mechanical stimulus to trigger mechanoadaptation
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