Matching Estimators of Causal Effects in Clustered Observational Studies with Application to Quantifying the Impact of Marine Protected Areas on Biodiversity

Marine conservation preserves fish biodiversity, protects marine and coastal ecosystems, and supports climate resilience and adaptation. Despite the importance of establishing marine protected areas (MPAs), research on the effectiveness of MPAs with different conservation policies is limited due to the lack of quantitative MPA information. In this paper, leveraging a global MPA database, we investigate the causal impact of MPA policies on fish biodiversity. To address challenges posed by this clustered and confounded observational study, we construct a matching estimator of the average treatment effect and a cluster-weighted bootstrap method for variance estimation. We establish the theoretical guarantees of the matching estimator and its variance estimator. Under our proposed matching framework, we recommend matching on both cluster-level and unit-level covariates to achieve efficiency. The simulation results demonstrate that our matching strategy minimizes the bias and achieves the nominal confidence interval coverage. Applying our proposed matching method to compare different MPA policies reveals that the no-take policy is more effective than the multi-use policy in preserving fish biodiversity.Comment: 25 pages, 4 figure

Tuneable denture adhesives using biomimetic principles for enhanced tissue adhesion in moist environments

Nature provides many interesting examples of adhesive strategies. Of particular note, the protein glue secreted by marine mussels delivers high adhesion in wet and dynamic environments owing to existence of catechol moieties. As such, this study focuses on denture fixatives, where a non-zinc-containing commercial-based formulation has been judiciously modified by a biomimetic catechol-inspired polymer, poly(3,4-dihydroxystyrene/styrene-alt-maleic acid) in a quest to modulate adhesive performance. In vitro studies, in a lap-shear configuration, revealed that the catechol-modified components were able to enhance adhesion to both the denture base and hydrated, functional oral tissue mimic, with the resulting mode of failure prominently being adhesive rather than cohesive. These characteristics are desirable in prosthodontic fixative applications, for which temporary adhesion must be maintained, with ultimately an adhesive failure from the mucosal tissue surface preferred. These insights provide an experimental platform in the design of future biomimetic adhesive systems. Statement of Significance: Mussel adhesive proteins have proven to be promising biomimetic adhesive candidates for soft tissues and here for the first time we have adapted marine adhesive technology into a denture fixative application. Importantly, we have incorporated a soft tissue mimic in our in vitro adhesion technique that more closely resembles the oral mucosa than previously studied substrates. The novel biomimetic-modified adhesives showed the ability to score the highest adhesive bonding out of all the formulations included in this study, across all moisture levels.This paper will be of major interest to the Acta Biomaterialia readership since the study has illustrated the potential of biomimetic principles in the design of effective prosthodontic tissue adhesives in a series of purpose-designed in vitro experiments in the context of the challenging features of the oral environment

Residency Times and Patterns of Movement of Postbreeding Dunlin on a Subarctic Staging Area in Alaska

Understanding how individuals use key resources is critical for effective conservation of a population. The Yukon-Kuskokwim Delta (YKD) in western Alaska is the most important postbreeding staging area for shorebirds in the subarctic North Pacific, yet little is known about movements of shorebirds there during the postbreeding period. To address this information gap, we studied residency times and patterns of movement of 17 adult and 17 juvenile radio-marked Dunlin (Calidris alpina) on the YKD between early August and early October 2005. Throughout this postbreeding period, during which Dunlin were molting, most birds were relocated within a 130 km radius of their capture site on the YKD, but three birds were relocated more than 600 km to the south at estuaries along the Alaska Peninsula. On average, juvenile Dunlin were relocated farther away from the banding site (median relocation distance = 36.3 km) than adult Dunlin (median relocation distance = 8.8 km). Post-capture, minimum lengths of stay by Dunlin on the YKD were not significantly different between juveniles (median = 19 days) and adults (median = 23 days), with some birds staging for more than 50 days. Body mass at time of capture was the best single variable explaining length of stay on the YKD, with average length of stay decreasing by 2.5 days per additional gram of body mass at time of capture. Conservation efforts for postbreeding shorebirds should consider patterns of resource use that may differ not only by age cohort but also by individual condition.Pour donner lieu à la conservation efficace d’une population, il est essentiel de comprendre comment les individus se servent des ressources importantes. Le delta Yukon-Kuskokwim, dans l’ouest de l’Alaska, est l’escale de post-reproduction la plus importante des oiseaux de rivage du Pacifique Nord subarctique. Pourtant, on en sait peu sur les déplacements des oiseaux de rivage à cet endroit pendant la période de post-reproduction. Afin de combler ce manque d’information, nous avons étudié les durées de résidence et les habitudes de déplacement de 17 bécasseaux variables (Calidris alpina) adultes et de 17 bécasseaux variables juvéniles radio-marqués dans le delta Yukon-Kuskokwim du début août au début octobre 2005. Pendant la période de post-reproduction pendant laquelle les bécasseaux variables muaient, la plupart des oiseaux ont été déplacés dans un rayon de 130 km de leur lieu de capture dans le delta Yukon-Kuskokwim, mais trois oiseaux ont été relocalisés à plus de 600 km vers le sud, aux estuaires le long de la péninsule de l’Alaska. En moyenne, les bécasseaux variables juvéniles ont été déplacés plus loin du lieu de baguage (distance de déplacement médiane = 36,3 km) que les bécasseaux variables adultes (distance de déplacement médiane = 8,8 km). Par bécasseau variable, les durées de séjour minimales après la capture au delta Yukon-Kuskokwim ne différaient pas considérablement entre les juvéniles (médiane = 19 jours) et les adultes (médiane = 23 jours), certains oiseaux faisant escale pendant plus de 50 jours. La masse corporelle au moment de la capture était la meilleure et la seule variable expliquant la durée du séjour au delta Yukon-Kuskokwim, la durée moyenne du séjour diminuant de 2,5 jours par gramme supplémentaire de masse corporelle au moment de la capture. Les efforts de conservation des oiseaux de rivage en période de post-reproduction devraient tenir compte des modèles d’utilisation des ressources qui risquent de différer non seulement en fonction de la cohorte d’âge, mais également en fonction de l’état de l’individu

Genes of the serotonergic and dopaminergic pathways and their interaction affect the expression of Behavioural and Psychological Symptoms in Dementia (BPSD).

Although there is evidence for the involvement of genes of serotonergic and dopaminergic systems in the manifestation of the Behavioural and Psychological Symptoms in Dementia (BPSD), genetic association studies are contradictory. We used 1008 probable AD patients from the UK and applied a Multiple Indicators Multiple Causes (MIMIC) approach to investigate the effect of 11 polymorphisms in the serotonergic and dopaminergic systems, on four behavioural sub-phenotypes, namely "psychosis"," moods", "agitation" and "behavioural dyscontrol", as well as on 12 NPI items. Significant findings included the association of DRD1 A48G with "psychosis" (p=0.037), the association of DAT1 VNTR with "agitation" (p=0.006) and the association of DRD4 with "moods" sub-phenotype (p=0.008). In addition, associations were identified between DRD1 A48G and DAT1 VNTR with aberrant motor behaviour (AMB) symptoms (p=0.001 and p=0.015 respectively), between DRD4 and sleep disturbances (p=0.018) and between 5HTTLPR and apathy (p=0.033). Finally, significant interactions were observed between COMT Val158Met and 5HTTLPR with "psychosis" (p=0.026), between HTTLPR and STin2 with "psychosis" (p=0.005), between DAT1 3'UTR VNTR and COMT Val158Met with "agitation" (p=0.0001) and between DAT1 3'UTR VNTR and 5HTTLPR with the "moods" factor (p=0.0027). The complexity of the interrelations between genetic variation, behavioural symptoms and clinical variables was efficiently captured by this MIMIC model

An Economic Examination of Potential Ethanol Production in Texas

Agribusiness, Agricultural and Food Policy, Resource /Energy Economics and Policy,

HIV incidence in men who have sex with men in England and Wales 2001-10: a nationwide population study.

BACKGROUND: Control of HIV transmission could be achievable through an expansion of HIV testing of at-risk populations together with ready access and adherence to antiretroviral therapy. To examine whether increases in testing rates and antiretroviral therapy coverage correspond to the control of HIV transmission, we estimated HIV incidence in men who have sex with men (MSM) in England and Wales since 2001. METHODS: A CD4-staged back-calculation model of HIV incidence was used to disentangle the competing contributions of time-varying rates of diagnosis and HIV incidence to observed HIV diagnoses. Estimated trends in time to diagnosis, incidence, and undiagnosed infection in MSM were interpreted against a backdrop of increased HIV testing rates and antiretroviral-therapy coverage over the period 2001-10. FINDINGS: The observed 3·7 fold expansion in HIV testing in MSM was mirrored by a decline in the estimated mean time-to-diagnosis interval from 4·0 years (95% credible interval [CrI] 3·8-4·2) in 2001 to 3·2 years (2·6-3·8) by the end of 2010. However, neither HIV incidence (2300-2500 annual infections) nor the number of undiagnosed HIV infections (7370, 95% CrI 6990-7800, in 2001, and 7690, 5460-10 580, in 2010) changed throughout the decade, despite an increase in antiretroviral uptake from 69% in 2001 to 80% in 2010. INTERPRETATION: CD4 cell counts at HIV diagnosis are fundamental to the production of robust estimates of incidence based on HIV diagnosis data. Improved frequency and targeting of HIV testing, as well as the introduction of ART at higher CD4 counts than is currently recommended, could begin a decline in HIV transmission among MSM in England and Wales. FUNDING: UK Medical Research Council, UK Health Protection Agency

The longitudinal variation of equatorial waves due to propagation on a varying zonal flow

The general 1-D theory of waves propagating on a zonally varying flow is developed from basic wave theory, and equations are derived for the variation of wavenumber and energy along ray paths. Different categories of behaviour are found, depending on the sign of the group velocity (cg) and a wave property, B. For B positive the wave energy and the wave number vary in the same sense, with maxima in relative easterlies or westerlies, depending on the sign of cg. Also the wave accumulation of Webster and Chang (1988) occurs where cg goes to zero. However for B negative they behave in opposite senses and wave accumulation does not occur. The zonal propagation of the gravest equatorial waves is analysed in detail using the theory. For non-dispersive Kelvin waves, B reduces to 2, and analytic solution is possible. B is positive for all the waves considered, except for the westward moving mixed Rossby-gravity (WMRG) wave which can have negative as well as positive B. Comparison is made between the observed climatologies of the individual equatorial waves and the result of pure propagation on the climatological upper tropospheric flow. The Kelvin wave distribution is in remarkable agreement, considering the approximations made. Some aspects of the WMRG and Rossby wave distributions are also in qualitative agreement. However the observed maxima in these waves in the winter westerlies in the eastern Pacific and Atlantic are not consistent with the theory. This is consistent with the importance of the sources of equatorial waves in these westerly duct regions due to higher latitude wave activity

Effects of bark beetle outbreaks on forest landscape pattern in the southern rocky mountains, U.S.A.

Since the late 1990s, extensive outbreaks of native bark beetles (Curculionidae: Scolytinae) have affected coniferous forests throughout Europe and North America, driving changes in carbon storage, wildlife habitat, nutrient cycling, and water resource provisioning. Remote sensing is a cru-cial tool for quantifying the effects of these disturbances across broad landscapes. In particular, Landsat time series (LTS) are increasingly used to characterize outbreak dynamics, including the presence and severity of bark beetle-caused tree mortality, though broad-scale LTS-based maps are rarely informed by detailed field validation. Here we used spatial and temporal information from LTS products, in combination with extensive field data and Random Forest (RF) models, to develop 30-m maps of the presence (i.e., any occurrence) and severity (i.e., cumulative percent basal area mortality) of beetle-caused tree mortality 1997–2019 in subalpine forests throughout the Southern Rocky Mountains, USA. Using resultant maps, we also quantified spatial patterns of cumulative tree mortality throughout the region, an important yet poorly understood concept in beetle-affected forests. RF models using LTS products to predict presence and severity performed well, with 80.3% correctly classified (Kappa = 0.61) and R2 = 0.68 (RMSE = 17.3), respectively. We found that ≥10,256 km2 of subalpine forest area (39.5% of the study area) was affected by bark beetles and 19.3% of the study area experienced ≥70% tree mortality over the twenty-three year period. Variograms indi-cated that severity was autocorrelated at scales \u3c 250 km. Interestingly, cumulative patch-size dis-tributions showed that areas with a near-total loss of the overstory canopy (i.e., ≥90% mortality) were relatively small (\u3c0.24 km2) and isolated throughout the study area. Our findings help to in-form an understanding of the variable effects of bark beetle outbreaks across complex forested regions and provide insight into patterns of disturbance legacies, landscape connectivity, and susceptibility to future disturbance

“To tell you the truth I’m tired”: a qualitative exploration of the experiences of ethnically diverse NHS staff

Objectives The aim of this paper was to explore the experiences and support needs of ethnically diverse healthcare staff and how they were affected by the COVID-19 pandemic. Design A qualitative study using focus groups conducted remotely on Microsoft Teams. Setting The study took place across 10 National Health Service Trusts in England; 5 were Acute Hospitals Trusts and 5 were Community and Mental Health Trusts. Participants 55 participants across 16 focus groups took part in the study. Participants were all healthcare staff members from ethnically diverse backgrounds. Results Seven themes were generated which highlighted issues of negative experiences of discrimination at work, particularly during the COVID-19 pandemic, including participants often finding line managers unsupportive, appearing to lack care and compassion, and not understanding ethnic diversity issues. Participants identified many reasons for finding it difficult to speak up when faced with such experiences, such as feeling unsafe to do so, or feeling too exhausted to keep speaking up. Other staff had more positive experiences and described supportive interventions, and despite workplace difficulties, many participants discussed remaining motivated to work in the National Health Service. Conclusions Negative day-to-day experiences of ethnically diverse healthcare staff, and the difficulty of speaking up about these align with other, international literature on this topic. Progress in the area of staff equality is vital if healthcare organisations are to continue to provide high-quality patient care and retain skilled, compassionate staff who value their place of work. Recent literature suggests that many initiatives to reduce inequalities have not been successful, and there is a call for fundamental, cultural-level change. Future research is needed to understand how best to implement these organisational-level changes and to evaluate their effectiveness