Quantifying physiological influences on otolith microchemistry

Trace element concentrations in fish earstones (‘otoliths’) are widely used to discriminate spatially discrete populations or individuals of marine fish, based on a commonly held assumption that physiological influences on otolith composition are minor, and thus variations in otolith elemental chemistry primarily reflect changes in ambient water chemistry. We carried out a long-term (1-year) experiment, serially sampling seawater, blood plasma and otoliths of mature and immature European plaice (Pleuronectes platessa L.) to test relationships between otolith chemistry and environmental and physiological variables. Seasonal variations in otolith elemental composition did not track seawater concentrations, but instead reflected physiological controls on metal transport and biokinetics, which are likely moderated by ambient temperature. The influence of physiological factors on otolith composition was particularly evident in Sr/Ca ratios, the most widely used elemental marker in applied otolith microchemistry studies. Reproduction also triggered specific variations in otolith and blood plasma metal chemistry, especially Zn/Ca ratios in female fish, which could potentially serve as retrospective spawning indicators. The influence of physiology on the trace metal composition of otoliths may explain the success of microchemical stock discrimination in relatively homogenous marine environments, but could complicate alternative uses for trace element compositions in biominerals of higher organism

\u3cem\u3eDrosophila\u3c/em\u3e Vitelline Membrane Assembly: A Critical Role for an Evolutionarily Conserved Cysteine in the “VM domain” of sV23

The vitelline membrane (VM), the oocyte proximal layer of the Drosophila eggshell, contains four major proteins (VMPs) that possess a highly conserved “VM domain” which includes three precisely spaced, evolutionarily conserved, cysteines (CX7CX8C). Focusing on sV23, this study showed that the three cysteines are not functionally equivalent. While substitution mutations at the first (C123S) or third (C140S) cysteines were tolerated, females with a substitution at the second position (C131S) were sterile. Fractionation studies showed that sV23 incorporates into a large disulfide linked network well after its secretion ceases, suggesting that post-depositional mechanisms are in place to restrict disulfide bond formation until late oogenesis, when the oocyte no longer experiences large volume increases. Affinity chromatography utilizing histidine tagged sV23 alleles revealed small sV23 disulfide linked complexes during the early stages of eggshell formation that included other VMPs, namely sV17 and Vml. The early presence but late loss of these associations in an sV23 double cysteine mutant suggests that reorganization of disulfide bonds may underlie the regulated growth of disulfide linked networks in the vitelline membrane. Found within the context of a putative thioredoxin active site (CXXS) C131, the critical cysteine in sV23, may play an important enzymatic role in isomerizing intermolecular disulfide bonds during eggshell assembly

Lean in healthcare: The unfilled promise?

In an effort to improve operational efficiency, healthcare services around the world have adopted process improvement methodologies from the manufacturing sector, such as Lean Production. In this paper we report on four multi-level case studies of the implementation of Lean in the English NHS. Our results show that this generally involves the application of specific Lean ‘tools’, such as ‘kaizen blitz’ and ‘rapid improvement events’, which tend to produce small-scale and localised productivity gains. Although this suggests that Lean might not currently deliver the efficiency improvements desired in policy, the evolution of Lean in the manufacturing sector also reveals this initial focus on the ‘tool level’. In moving to a more system-wide approach, however, we identify significant contextual differences between healthcare and manufacturing that result in two critical breaches of the assumptions behind Lean. First, the customer and commissioner in the private sector are the one and the same, which is essential in determining ‘customer value’ that drives process improvement activities. Second, healthcare is predominantly designed to be capacity-led, and hence there is limited ability to influence demand or make full use of freed-up resources. What is different about this research is that these breaches can be regarded as not being primarily ‘professional’ in origin but actually more ‘organisational’ and ‘managerial’ and, if not addressed could severely constrain Lean’s impact on healthcare productivity at the systems level

Global cocaine intoxication research trends during 1975–2015: a bibliometric analysis of Web of Science publications

Density view of terms map based on the co-occurrence matrix of terms from text data in the title and abstract of retrieved publications related to cocaine toxicity by periods. Figure S1. Density view of terms map in Period I (1975–1995); colors show the density of relevance, sorting from blue (lowest density) to red (highest density). (number of publications related to cocaine intoxication = 954). Figure S2. Density view of terms map in Period II (1996–2005); colors show the density of relevance, sorting from blue (lowest density) to red (highest density). (Number of publications related to cocaine intoxication = 987). Figure S3. Density view of terms map in Period III (2006–2015); colors show the density of relevance, sorting from blue (lowest density) to red (highest density). (Number of publications related to cocaine intoxication = 961). Figure S4. Density view of terms map in Period 1975–1995; colors show the density of relevance, sorting from blue (lowest density) to red (highest density). (Number of publications related to cocaine intoxication = 2,902). (DOCX 794 kb

Between a rock and a hard place of geopolitically sensitive threats – critical incidents and decision inertia

While the SAFE-T model of decision making emphasizes naturalistic decision making, its potential for cross-comparative analysis of incidents with global implications remains underutilized, which the current paper aims to address. To this end, it draws upon open-source reports from unclassified American, British and Russian intelligence reports to explore the management of three types of 10 high-profile geopolitically sensitive threats from across the globe (verifying potential terrorist identity, hostage rescue and national/international security). Defining features of such incidents include decision makers’ ability to prospectively model competing scenarios in which they must select between options and where every outcome looks aversive and high risk (‘damned if you do or damned if you don’t decisions’). A frequent consequence of such calculations is ‘decision inertia’ (a failure to execute an important, irrevocable decision resulting in non-optimal consequences), or ‘implementation failure’ (a failure to make a choice). Combining the benefit of the theoretical framework and hindsight knowledge of the analyzed incidents, the paper facilitates theoretical understanding of decision inertia and failures to act. Encouraging the consideration of multiple scenario endings contingent on a wide spectrum of factors and unique cultural-historical context, it also helps identify past decision errors in order to inform assessment and management of similar geopolitical threats in the future

A qualitative study of professional and carer perceptions of the threats to safe hospital discharge for stroke and hip fracture patients in the English National Health Service

Background: Hospital discharge is a vulnerable transitional stage in patient care. This qualitative study investigated the views of healthcare professionals and patients about the threats to safe hospital discharge with aim of identifying contributory and latent factors. The study was undertaken in two regional health and social care systems in the English National Health Service, each comprising three acute hospitals, community and primary care providers and municipal social care services. The study focused on the threats to safe discharge for hip fracture and stroke patients as exemplars of complex care transitions. Methods: A qualitative study involving narrative interviews with 213 representative stakeholders and professionals involved in discharge planning and care transition activities. Narratives were analysed in line with ‘systems’ thinking to identify proximal (active) and distal (latent) factors, and the relationships between them. Results: Three linked categories of commonly and consistently identified threat to safe discharge were identified:(1) ‘direct’ patient harms comprising falls, infection, sores and ulceration, medicines-related issues, and relapse; (2) proximal ‘contributing’ factors including completion of tests, assessment of patient, management of equipment and medicines, care plan, follow-up care and patient education; and distal ‘latent’ factors including discharge planning, referral processes, discharge timing, resources constraints, and organisational demands. Conclusion: From the perspective of stakeholders, the study elaborates the relationship between patient harms and systemic factors in the context of hospital discharge. It supports the importance of communication and collaboration across occupational and organisational boundaries, but also the challenges to supporting such communication with the inherent complexity of the care system