To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Radiocarbon (14C) is one of the key radionuclides for the performance and safety assessment of a radioactive waste disposal, due to its high activity concentration in waste materials from the nuclear cycle and to its mobility. The measurement of the 14C content in spent ion exchange resins from nuclear reactors is important for the safety assessment of the disposal concept and for the choice of the appropriate treatment/disposal method. Ion exchange resins are commonly used in nuclear reactors as filters for the purification of process liquids or wastes streams and they retain molecules containing radioactive isotopes, among which is 14C. Their efficiency, both as filters and as waste containers, is strictly connected with the morphology. The preservation of spherical shape upon aging is one of the key parameters for their quality assessment and for the evaluation of the potential release of 14C during storage conditions. In this study, the change in IERs morphology during storage periods has been investigated in order to verify correlation with 14C release. Both brand new and aged specimens have been studied in order to assess the quality of the resins after 10 yr of storage and to contribute to the understanding of 14C release mechanisms.
A preliminary evaluation of gaseous radiocarbon (14C) behavior under geological repository conditions for Italian radioactive high level waste-long-lived and intermediate level waste disposal has been performed. Although in Italy there is still no defined project for a geological disposal facility, current work may support future safety assessment studies for a hypothetical future repository in deep salt rock. In the Italian context of radioactive waste, the percentage of 14C bearing waste to be disposed in a possible geological repository is low; irradiated graphite is the most important radiological source. Data about the radiological inventory has been collected to simulate production and migration of gaseous 14C in a hypothetical geological repository. Three different conceptual models have been developed and simulated. The first model has considered a preliminary evaluation of the radiological impact referred to the whole inventory; the second and third model have evaluated the impact only due to the irradiated graphite. A preliminary sensitivity analysis has been carried out, highlighting the importance of geometry and of distribution coefficients (Kd) in materials used to seal the disposal underground facility. Results show the possibility to correlate the Kd values, the volume and the location of the sealing materials to the amount of 14C migrating toward the surface.
To evaluate the organizational processes that influence the quality of care for patients with multimorbidity at nurse practitioner-led clinics (NPLCs).
People are living longer, most with one or more chronic diseases (mulitmorbidity) and primary healthcare for these patients has become increasingly complex. One response was the establishment of new models of primary healthcare. NPLCs are an example of a model developed in Ontario, Canada, which feature nurse practitioners as the primary care providers practicing within an interprofessional team. Evaluation of the extent to which the processes within NPLC model addressed the needs of patients with multimorbidity is warranted.
Eight nurse practitioners were interviewed to determine their perception of the quality of care provided to patients with multimorbidity at NPLCs. Interpretive description guided the analysis and themes were identified.
Three themes arose from the analysis, each of which has an impact on the quality of care. The level of patient vulnerability at the NPLCs was high resulting in the need to address social and financial issues before the care of chronic conditions. Dynamics within the interprofessional team impacted the quality of patient care, including NP recruitment and retention, leaves of absence and turnover in staff at the NPLCs had an effect on interprofessional team functioning and patient care. Finally, coordination of care at the NPLCs, such as length of appointments, determined the extent to which attention was given to individual clinical issues was a factor. Strategies to address social determinants of health and for recruitment and retention of NPs is essential for improved quality of care. Comprehensive orientation to the interprofessional team as well as flexibility in care processes may also have positive effects on the quality of care of patients with complex clinical issues.
This article traces the planning history of two central marketplaces in sub-Saharan Africa, in Dakar and Kinshasa, from their French and Belgian colonial origins until the post-colonial period. In the (post-)colonial city, the marketplace has always been at the centre of contemporary debates on urban identity and spatial production. Using a rich variety of sources, this article makes a contribution to a neglected area of scholarship, as comparative studies on planning histories in sub-Saharan African cities are still rare. It also touches upon some key issues such as the multiple and often intricate processes of urban agency between local and foreign actors, sanitation and segregation, the different (post-)colonial planning cultures and their limits and the role of indigenous/intermediary groups in spatial contestation and reappropriation.
Meningitis with a negative cerebrospinal fluid Gram stain (CSF-GS) poses a diagnostic challenge as more than 50% of patients remain without an aetiology. The introduction of polymerase chain reaction (PCR) and arboviral serologies have increased diagnostic capabilities, yet large scale epidemiological studies evaluating their use in clinical practice are lacking. We conducted a prospective observational study in New Orleans between November 1999 and September 2008 (early era) when PCR was not widely available, and in Houston between November 2008 and June 2013 (modern era), when PCR was commonly used. Patients presenting with meningitis and negative CSF-GS were followed for 4 weeks. All investigations, PCR used, and results were recorded as they became available. In 323 patients enrolled, PCR provided the highest diagnostic yield (24·2%) but was ordered for 128 (39·6%) patients; followed by serology for arboviruses (15%) that was ordered for 100 (31%) of all patients. The yield of blood cultures was (10·3%) and that of CSF cultures was 4%; the yield for all other tests was <10%. Overall, 65% of the patients remained without a diagnosis at 4 weeks: 72·1% in early era vs. 53·4% (P < 0·01) in modern era; this change was attributed to diagnosing more viral pathogens, 8·3% and 26·3% (P < 0·01), respectively. The introduction of PCR and arboviral serologies has improved the yield of diagnosing patients with meningitis and a negative CSF-GS, but both tests are being under-utilized.
Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes pneumonia in immunocompromised humans and severe pulmonary damage in patients with cystic fibrosis. Imbalanced fatty acid incorporation in membranes, including increased arachidonic acid and decreased DHA concentrations, is known to play a critical role in chronic inflammation associated with bacterial infection. Other lipids, such as EPA and alkylglycerols, are also known to play a role in inflammation, particularly by stimulating the immune system, decreasing inflammation and inhibiting bacterial growth. In this context, the goal of the present study was to assess the effect of dietary DHA/EPA, in a 2:1 ratio, and alkylglycerols, as natural compounds extracted from oils of rays and chimeras, respectively, on the inflammatory reaction induced by P. aeruginosa pulmonary infection in mice. To this end, mice were fed with a control diet or isolipidic, isoenergetic diets prepared with oils enriched in DHA/EPA (2:1) or alkylglycerols for 5 weeks before the induction of acute P. aeruginosa lung infection by endotracheal instillation. In our model, DHA/EPA (2:1) significantly improved the survival of mice after infection, which was associated with the acceleration of bacterial clearance and the resolution of inflammation leading to the improvement of pulmonary injuries. By contrast, alkylglycerols did not affect the outcomes of P. aeruginosa infection. Our findings suggest that supplementation with ray oil enriched in DHA/EPA (2:1) can be considered as a preventive treatment for patients at risk for P. aeruginosa infection.
Consider an autoregressive model with measurement error: we observe Zi =
εi, where the
unobserved Xi is a stationary
solution of the autoregressive equation Xi =
− 1) + ξi. The
regression function gθ0 is
known up to a finite dimensional parameter θ0 to be estimated. The distributions of
ξ1 and X0 are unknown
and gθ belongs to a large
class of parametric regression functions. The distribution of ε0 is completely
known. We propose an estimation procedure with a new criterion computed as the Fourier
transform of a weighted least square contrast. This procedure provides an asymptotically
θ̂ of θ0, for a large class of regression
functions and various noise distributions.
This article analyses how the events of the late 1960s – and in particular the Nigeria–Biafra War – marked a turning point in the history of the International Committee of the Red Cross (ICRC). The Nigeria-Biafra conflict required the ICRC to set up and coordinate a major relief operation during a civil war in a post-colonial context, posing several new challenges for the organisation. This article shows how the difficulties encountered during the conflict highlighted the need for the Geneva-based organisation to reform the management of its operations, personnel, and communications in order to become more effective and professional. Finally, the article takes the examination of this process within the ICRC as a starting point for a broader discussion of the changing face of the humanitarian sector in the late 1960s.
To evaluate the association between food and nutrition insecurity and asthma in children from Latin America.
São Francisco do Conde, Bahia, north-eastern Brazil.
The study included 1307 children aged 6–12 years from public elementary schools. Asthma symptoms were collected using a questionnaire that was translated and adapted from the International Study of Asthma and Allergies in Childhood, phase III. The diagnosis of asthma was determined based on reports of wheezing in the previous 12 months. The Brazilian Food Insecurity Scale was used to identify food insecurity. We also obtained demographic, socio-economic and anthropometric information for each participant. We used multivariate logistic regression analyses to assess the associations of interest.
Of the children surveyed, 10·4 % had a history of wheezing and 64·5 % had some degree of food and nutrition insecurity. We found a positive dose–response relationship and statistically significant associations of asthma with moderate (OR = 1·71, 95 % CI 1·01, 2·89) and severe (OR = 2·51, 95 % CI 1·28, 4·93) food and nutrition insecurity.
The results show that moderate and severe food and nutrition insecurity are markers of vulnerability to wheezing. It is important to note that the results of studies in this field have potential implications for social policies that promote food security. Further studies to identify the mechanisms involved in the relationship between food and nutrition insecurity and asthma are needed.
The hidden nature of older adult mistreatment renders its detection in the domestic setting particularly challenging. A validated screening instrument that can provide a systematic assessment of risk factors can facilitate this detection. One such instrument, the “expanded Indicators of Abuse” tool, has been previously validated in the Hebrew language in a hospital setting. The present study has contributed to the validation of the “e-IOA” in an English-speaking community setting in Ontario, Canada. It consisted of two phases: (a) a content validity review and adaptation of the instrument by experts throughout Ontario, and (b) an inter-rater reliability assessment by home visiting nurses. The adaptation, the “Mistreatment of Older Adult Risk Factors” tool, offers a comprehensive tool for screening in the home setting. This instrument is significant to professional practice as practitioners working with older adults will be better equipped to assess for risk of mistreatment.
Objectives: In recent years, there has been growth in the use of health technology assessment (HTA) for making decisions about the reimbursement, coverage, or guidance on the use of health technologies. Given this greater emphasis on the use of HTA, it is important to develop standards of good practice and to benchmark the various HTA organizations against these standards.
Methods: This study discusses the conceptual and methodological challenges associated with benchmarking HTA organizations and proposes a series of audit questions based on a previously published set of principles of good practice.
Results and Conclusions: It is concluded that a benchmarking exercise would be feasible and useful, although the question of who should do the benchmarking requires further discussion. Key issues for further research are the alternative methods for weighting the various principles and for generating an overall score, or summary statement of adherence to the principles. Any weighting system, if developed, would need to be explored in different jurisdictions to assess the extent to which the relative importance of the principles is perceived to vary. Finally, the development and precise wording of the audit questions requires further study, with a view to making the questions as unambiguous as possible, and the reproducibility of the assessments as high as possible.
The ion beam synthesis of Pb nanoparticles (NPs) in silica/silicon films is studied in terms of the combination of a two-step annealing process consisting of a low temperature long time aging treatment followed by a high temperature short time furnace annealing. The samples are analyzed through Rutherford Backscattering Spectrometry and Transmission Electron Microscopy. The aging process leads to the suppression of the classical homogeneous nucleation of metallic Pb NPs in the silica, thus promoting Pb redistribution during the high temperature annealing. This causes the formation of dense bi-dimensional NP arrays located at the silica-silicon interface, presenting small size dispersion.
In this paper, we report a novel method to improve aluminum interconnect electromigration performance, reduce metal line sheet resistance (Rs) and reduce via contact resistance (Rc) in a minimum pitch design. We report the effects of bottom redundancy layers on electrical line and via resistance and upstream electromigration performance. We studied 4 metallization stacks: (I) Ti/TiN/AlCu/Ti/TiN, (II) Ti/TiN/Ti/AlCu/Ti/TiN (annealed at 400°C for 20 minutes), (III) a flash process/stack I, (IV) stack III with aluminum deposition temperature of 250°C. Aluminum deposition temperature in stacks I, II, and III are 200°C. Bottom Ti/TiN, AlCu, and Top Ti/TiN layers have the same thickness for all these stacks. Metal line Rs and via contact resistances (Rc) of stack IV are 5% and 10% lower, respectively, than stack I. Stack II metal line sheet resistance is 15% higher than stack I, which is attributed to Al consumption in the TiAl3 formation during 400°C/20minutes annealing. Electromigration performance is best with stack IV followed by III, II, then I.