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On December 1, 2022, the International Court of Justice (ICJ) rendered its judgment in the Dispute Concerning the Status and Use of the Waters of the Silala (Chile v. Bolivia). There is no basin agreement governing the Silala, and Chile and Bolivia have ratified neither the 1997 Convention on the Law of Non-Navigational Uses of International Watercourses nor the 1992 Convention on the Protection and Use of Transboundary Watercourses and International Lakes. In the absence of a treaty regime applicable to the waters of the Silala River, the Court had the opportunity in this case to consider the legal framework applicable to international watercourses under customary international law.
On December 15, 2022, the International Criminal Court's Appeals Chamber unanimously confirmed Dominic Ongwen's convictions for crimes against humanity and war crimes and, by majority vote, confirmed his sentence of twenty-five years' imprisonment.
Arthropod species diversity enhances ecosystem productivity and sustainability by increasing pollination and biological control services. Although, it is declining rapidly due to conventional agricultural intensification, organic agriculture with reduced reliance on agronomic inputs can regenerate ecosystems' resilience and restore them. Here, we report whether hexapod communities differ on both types of farming systems in small-scale field plot experiments, wherein Maize variety AG-589 was grown organically and conventionally in the 2020 and 2021 seasons. Livestock manure was applied in organic fields, whereas nitrogen and phosphorous were used as synthetic fertilizers in conventional fields. Hexapods were sampled three weeks after sowing once a week from the middle rows of subplots from both organically and conventionally grown maize. Twelve species of herbivores and four species of predators were recorded. Hexapod abundance overall and that of herbivores only was higher in conventionally cultivated maize, while predator abundance was higher in organic maize. Herbivores species diversity and evenness were significantly higher in conventional maize. Predator species diversity and evenness were significantly higher in organic maize fields. We noted predator abundance, diversity, and evenness as strong predictors to lower herbivore populations. These findings suggest that organic farming conserves natural enemies’ biodiversity and regulates herbivores with increased provision of suitable habitats and prey resources for natural enemies, leading to enhanced relative abundance in their specialized niches. Thus, organic agriculture can potentially mediate better ecosystem services.
War may raise the level of distress and post-traumatic stress disorder (PTSD). The study explores the extent to which 4 factors determine levels of PTSD and distress symptoms of Ukraine civilians (without developing PTSD) during the current war.
Method:
The data were collected via a Ukrainian internet panel company. 1001 participants responded to a structured online questionnaire. Path analysis was conducted to identify predictive indicators of PTSD scores.
Results:
PTSD symptoms positively correlated with respondents’ level of exposure to the war and their sense of danger, and negatively correlated with well-being, family income, and age. Females scored higher on PTSD symptoms. Path analysis showed that higher exposure to war and higher sense of danger increase PTSD and distress symptoms, whereas higher well-being, higher individual resilience, and being a man, as well as older age decrease their level. Despite the strong effects of the coping suppressing factors, most respondents did not reach the critical level of PTSD or distress symptoms.
Conclusion:
At least 4 positive and negative factors account for people’s coping with stressful experiences: previous traumatic experiences, individual level of pathology, personality attributes, and socio-demographic characteristics. The balance of these factors protects most people from PTSD symptoms despite their being affected by war traumas.
To undertake a healthcare-based multimodal evaluation of the combination of filtering facepiece respirator (FFR) with the elastic-band beard cover technique, including quantitative fit test (QNFT) results, skills assessment, and usability assessment.
Design and setting:
We conducted a prospective study through the Respiratory Protection Program at the Royal Melbourne Hospital from May 2022 to January 2023.
Participants:
Healthcare workers who required respiratory protection and could not shave for religious, cultural, or medical reasons.
Intervention:
Online education and personal face-to-face training on the use of FFR with the elastic-band beard cover technique.
Results:
Among 87 participants (median beard length 38 mm; interquartile range [IQR], 20–80), 86 (99%) passed 3 QNFTs consecutively with the elastic-band beard cover under a Trident P2 respirator and 68 (78%) passed 3 QNFTs consecutively with a 3M 1870+ Aura respirator. The first QNFT pass rate and the overall fit factors were significantly higher when using the technique than without the elastic-band beard cover. Most participants displayed a high skill level in their donning, doffing, and user seal-check techniques. Of 87 participants, 83 (95%) completed the usability assessment. The overall ease of use, comfort, and overall assessment were rated highly.
Conclusions:
The elastic-band beard cover technique can provide safe and effective respiratory protection for bearded healthcare workers. The technique was easily taught, comfortable, well tolerated and accepted by healthcare workers, potentially allowing them full participation in the workforce during pandemics with airborne transmission. We recommend further research and evaluation of this technique in a broader health workforce.
Open-air surface accumulations and scatters of material cultural remains often are perceived as less-reliable archaeological archives, where it is difficult to distinguish anthropogenic versus geogenic formation processes or to assess their specific effects on the integrity of archaeological records. Here we analyze the depositional histories of three Middle Paleolithic open-air sites in the Negev desert of Israel, combining archaeological and geomorphological methods to create a conceptual model of multi-scale effects on the archaeological remains. Relying on the long research history in archaeology and geomorphology in the Negev, we show that integration of archaeological and geomorphological methodologies provides nuanced insights to our understanding of the archaeological record. The links established between regional and local geomorphic processes and lithic taphonomy by applying such a multi-scale analysis further allow back-tracking environmental processes from flint taphonomic attributes. Placing each site within the range of regional and local processes of exposure and burial by using informed and critically evaluated data helps to create a robust regional archaeological data base. We suggest that our approach is useful in other arid zone contexts and may have implications for understanding Pleistocene population movements across such regions.
Communication changes following acquired brain injury (ABI) may necessitate use of augmentative and alternative communication (AAC). Speech pathologists regularly assist people with ABI and their families with AAC assessment and recommendations, as well as education and training on AAC use. To date, there has been no Australian research investigating the perspectives of speech pathologists working in the field of ABI and AAC. This research aimed to 1) Explore speech pathologists’ insights regarding enablers and barriers to considerations and uptake, and ongoing use, of AAC by people with ABI and 2) Understand their perspectives on AAC acceptance, abandonment and rejection.
Method:
A qualitative research design, with semi-structured interviews, was used with seven speech pathologists working across three Australian states. Interviews were transcribed verbatim, and thematically analysed. To triangulate results, the lived experience reflections of one co-author, who has an ABI and uses AAC, were drawn on.
Results:
Seven themes were identified, relating to four of the five domains of the World Health Organization’s assistive technology model. These included that AAC should be person-centred, with consideration of both products and personnel required, and with effective policy aiding AAC trial, uptake and use.
Conclusion:
This research has highlighted considerations for AAC use by people with ABI, from the perspective of speech pathologists and aided by lived experience reflections. Speech pathologists need to understand the breadth of products, and good practice service steps, to ensure successful AAC use and skill development. Listening to the perspectives of people with ABI is central to that understanding.
The development of novel drug delivery systems, which are revolutionizing modern medicine, is benefiting from studies on microorganisms’ swimming. In this paper we consider a model microorganism (a squirmer) enclosed in a viscous droplet to investigate the effects of medium heterogeneity or geometry on the propulsion speed of the caged squirmer. We first consider the squirmer and droplet to be spherical (no shape effects) and derive exact solutions for the equations governing the problem. For a squirmer with purely tangential surface velocity, the squirmer is always able to move inside the droplet (even when the latter ceases to move as a result of large fluid resistance of the heterogeneous medium). Adding radial modes to the surface velocity, we establish a new condition for the existence of a co-swimming speed (where squirmer and droplet move at the same speed). Next, to probe the effects of geometry on propulsion, we consider the squirmer and droplet to be in Newtonian fluids. For a squirmer with purely tangential surface velocity, numerical simulations reveal a strong dependence of the squirmer's speed on shapes, the size of the droplet and the viscosity contrast. We found that the squirmer speed is largest when the droplet size and squirmer's eccentricity are small, and the viscosity contrast is large. For co-swimming, our results reveal a complex, non-trivial interplay between the various factors that combine to yield the squirmer's propulsion speed. Taken together, our study provides several considerations for the efficient design of future drug delivery systems.
Increasing age and puberty affect the hypothalamic pituitary adrenal (HPA) axis maturation, which is likely associated with an increase in environmental demands (e.g., social) and vulnerability for the onset of psychiatric conditions (e.g., depression). There is limited research as to whether such patterns are consonant in youth with autism spectrum disorder (ASD), a condition marked by social challenges, dysregulation of the HPA axis, and higher rates of depression setting the stage for enhanced vulnerability during this developmental period.
The current study interrogated diurnal cortisol by examining (1) cortisol expression longitudinally over the pubertal transition between autistic and neurotypical youth, (2) the trajectory of diurnal cortisol and the unique contributions of age vs. puberty, and (3) potential sex differences. As hypothesized, results indicate autistic compared to typically developing youth demonstrate a shallower diurnal slope and elevated evening cortisol. These differences were in the context of higher cortisol and flatter rhythms based on age and pubertal development. Also, sex-based differences emerged such that females in both groups had higher cortisol, flatter slopes, and higher evening cortisol than males. The results show that despite the trait-like stability of diurnal cortisol, HPA maturation is impacted by age, puberty, sex, as well as an ASD diagnosis.
Increasing pressure – such as from conflict, climate change and urbanisation – on maritime cultural heritage in the Middle East and North Africa (MENA) led to the establishment of the Maritime Endangered Archaeology (MarEA) Project in 2019. This five-year programme aims to assess rapidly and comprehensively the vulnerability of maritime and coastal heritage in the MENA region and assist in its management in the face of the aforementioned challenges. The two case studies discussed in this article highlight some of the main aspects of MarEA's current work in North Africa by focusing on two different aspects of the methodological approach used: first, the generalised but comprehensive damage and threat assessment, as applied to all sites, and demonstrated for the historic port of Suakin (Sudan); second, site-specific shoreline change assessment for the purpose of assessing the impact of coastal erosion, as demonstrated for the World Heritage Site of Sabratha (Libya).
Power minimisation of fluid transport in branched fluidic networks has become of paramount importance for microfluidics, additive manufacturing and hierarchical functional materials. For fully developed laminar flow of Newtonian fluids, Murray's theory provides a solution for the channel and network dimensions that minimise power consumption. However, design and optimisation of networks that transport complex fluids is still challenging. Here, we generalise Murray's theory towards fluid rheologies, including non-Newtonian (power-law) and yield-stress fluids (Bingham, Herschel–Bulkley, Casson). A straightforward graphical approach is presented that provides the optimal radii in a branching network, and the angles between these branches. The wall shear stress is found to be uniform over the entire network, and the velocity profile is self-similar. Furthermore, the effect of non-optimal channel radii on the power consumption of the network is investigated. Finally, examples illustrate how this approach applies to a wide variety of systems.
Shock buffet on wings is a phenomenon caused by strong shock-wave/boundary-layer interaction resulting first in self-sustained flow unsteadiness and eventually in a detrimental structural response called buffeting. While it is an important aspect of wing design and aircraft certification, particularly for modern transonic air transport, not all of the underlying multidisciplinary physics is thoroughly understood. Building upon a single-discipline shock-buffet stability study, this work now investigates the impact of an elastic structure in these extreme flow conditions. Specifically, a triglobal stability analysis of a fluid–structure coupled system is presented, utilising the implicitly restarted Arnoldi method with a sparse iterative Krylov solver and novel preconditioner. Asymmetry resulting from a static aeroelastic simulation based on a finite-element model of the underlying geometry in a wind tunnel modifies the global modes of the earlier fluid-only symmetric full-span analysis. A flutter stability analysis at wind-tunnel flow conditions below shock-buffet onset finds no instability in the structural degrees-of-freedom, whereas in shock-buffet flow with globally unstable fluid modes additional marginally unstable structural (and fluid) modes emerge. The developed stability tool for coupled analysis is instrumental in identifying those physically relevant and strongly coupled modes where a standard pk-type (p being eigenvalue and k reduced frequency) flutter analysis fails. With the complementary computation of adjoint eigenmodes, the core of the instability is pinpointed to a relatively small wing area which may help to effect the control and delay of this detrimental transonic unsteadiness. We contribute to the question on how the presence of the elastic wing structure impacts on the otherwise pure aerodynamic three-dimensional shock-buffet dynamics.
Boundary-layer flow over a realistic porous wall might contain both the effects of wall-permeability and wall-roughness. These two effects are typically examined in the context of a rough-wall flow, i.e. by defining a ‘roughness’ length or equivalent to capture the effect of the surface on momentum deficit/drag. In this work, we examine the hypothesis of Esteban et al. (Phys. Rev. Fluids, vol. 7, no. 9, 2022, 094603), that a turbulent boundary layer over a porous wall could be modelled as a superposition of the roughness effects on the permeability effects by using independently obtained information on permeability and roughness. We carry out wind tunnel experiments at high Reynolds number ($14\ 400 \leq Re_{\tau } \leq 33\ 100$) on various combinations of porous walls where different roughnesses are overlaid over a given permeable wall. Measurements are also conducted on the permeable wall as well as the rough walls independently to obtain the corresponding length scales. Analysis of mean flow data across all these measurements suggests that an empirical formulation can be obtained where the momentum deficit ($\Delta U^+$) is modelled as a combination of independently obtained roughness and permeability length scales. This formulation assumes the presence of outer-layer similarity across these different surfaces, which is shown to be valid at high Reynolds numbers. Finally, this decoupling approach is equivalent to the area-weighted power-mean of the respective permeability and roughness length scales, consistent with the approach recently suggested by Hutchins et al. (Ocean Engng, vol. 271, 2023, 113454) to capture the effects of heterogeneous rough surfaces.
For solitary bees, nesting substrate availability may limit population growth. Here, we investigate the nesting of a locally abundant bee Osmia conjuncta Cresson (Hymenoptera: Megachilidae) in empty shells of exotic snails, Cepaea spp. Held (Stylommatophora: Helicidae), in Hamilton, Ontario, Canada. A literature review determined that O. conjuncta was sparsely distributed throughout its range, with a low relative abundance except for the Niagara Region of Ontario, Canada, three sites in Maryland, United States of America, and the focal study area in Hamilton, Ontario. The Hamilton field survey of five grassland bee communities found O. conjuncta to be the most abundant bee species. The average relative abundance was 18.7%, peaking at 87% on one spring day. A survey of 1088 empty snail shells was done at the site with the highest O. conjuncta abundance. It revealed an average of 10.87 empty shells per square metre with cocoons in 9.8% of the shells, averaging 1.6 cocoons per nest. The relation between shell traits and cocoon presence indicated that O. conjuncta preferred nesting in shells with intermediate size and colour and avoided shells near shrubs. The presence of Cepaea snails increased O. conjuncta populations with potential consequences to the local bee assemblage.
Urbanisation has modified the distribution and community composition of mosquito species (Culicidae). Habitat disturbance may increase the risk of loss of species diversity and the occurrence of vector-borne diseases. Studies on the presence of larvae and the eco-physicochemical characteristics of water bodies near urban areas provide information on the risk of these diseases. In this study, the presence of larvae in different types of urban and periurban water bodies in Villahermosa City, Tabasco, Mexico was analysed. The eco-physicochemical characteristics of each collecting site were measured. A total of 67 528 larvae were collected, 1366 were identified to species, and 15 species were observed. Although Culex spp. were the most dominant species, Anopheles albimanus was the only species present in all habitats. Despite the large variability in the parameters measured (especially in physicochemical parameters; e.g., pH, electrical conductivity, total dissolved solids), differences were observed among the breeding sites. Weak correlations were found between eco-physicochemical parameters and species presence. Predators may have a major role in determining community processes in the region. Habitat disturbance may be responsible for eco-physicochemical variations altering mosquito community composition, resulting in the loss of endemic mosquito species and increasing the risk of vector-borne diseases in Villahermosa.
On March 11, 2004, Madrid suffered one of the worst terrorist attacks in the history of Spain, leaving more than 190 dead and 2,000 injured. For years, the psychological consequences of the attacks have been studied; however, its long-term effects on symptomatology and especially on well-being remains unknown. This study aims to explore, through a qualitative approach, pathways and obstacles to the well-being of those affected directly or indirectly by the attacks of March 11 in Madrid. Two focus groups were held, one for indirect victims and one for direct victims. Subsequently, a thematic analysis of the materials obtained was carried out. More than 10 years after the attacks, most of the participants reported great difficulty in achieving well-being. Acceptance and victims’ associations seemed to act as key facilitators, while symptoms, political institutions and the media were the main obstacles. Direct and indirect victims presented similar data although aspects such as guilt and family relationships played a different role in their well-being.
Smartphone applications are used widely in healthcare, including antimicrobial applications such as Microguide. There has been no review of hospitals using this smartphone application for ENT conditions.
Methods
This study analysed all hospital accounts using Microguide and examined the ENT conditions that were listed.
Results
In total, 123 hospitals were included in this study; 45 ENT-related conditions were listed on Microguide across all hospitals, with an average of 8 conditions listed per hospital.
Conclusion
There is a significant disparity of ENT conditions listed on Microguide. A suggested list is recommended to be included for ENT departments using Microguide, to help improve antimicrobial stewardship for the specialty.