bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitivity of aerosol radiative effects to different mixing assumptions in the AEROPT 1.0 submodel of the EMAC atmospheric-chemistry–climate model
Authors: Klingmüller K. , Steil B. , Brühl C. , Tost H. , Lelieveld J.
Published: October 2014

Abstract. The modelling of aerosol radiative forcing is a major cause of uncertainty in the assessment of global and regional atmospheric energy budgets and climate change. One reason is the strong dependence of the aerosol optical properties on the mixing state of aerosol components, such as absorbing black carbon and, predominantly scattering sulfates. Using a new column version of the aerosol optical properties and radiative-transfer code of the ECHAM/MESSy atmospheric-chemistry–climate model (EMAC), we study the radiative transfer applying various mixing states. The aerosol optics code builds on the AEROPT (AERosol OPTical properties) submodel, which assumes homogeneous internal mixing utilising the volume average refractive index mixing rule. We have extended the submodel to additionally account for external mixing, partial external mixing and multilayered particles. Furthermore, we have implemented the volume average dielectric constant and Maxwell Garnett mixing rule. We performed regional case studies considering columns over China, India and Africa, corroborating much stronger absorption by internal than external mixtures. Well-mixed aerosol is a good approximation for particles with a black-carbon core, whereas particles with black carbon at the surface absorb significantly less. Based on a model simulation for the year 2005, we calculate that the global aerosol direct radiative forcing for homogeneous internal mixing differs from that for external mixing by about 0.5 W m−2.
Small farm dams: impact on river flows and sustainability in a context of climate change
Authors: Habets F. , Philippe E. , Martin E. , David C. H. , Leseur F.
Published: October 2014

Abstract. The repetition of droughts in France has led to a growing demand for irrigation water and consequently to an increase in requests for the construction of small farm dams. Although such dams are small, their accumulation in a basin affects river flows, because the water collected in these small farm dams is used for irrigation and thus does not contribute to river flow. In order to gain more insight into their impact on the annual and monthly discharges, especially during dry years, a small farm dam model was built and connected to a hydrometeorological model. Several scenarios with different volume capacities, filling catchment sizes and filling periods were tested for such dams. The results were analysed in a small basin in western France, where the pressure for building such dams is high, and then extended to the entire country. It was found that, due to the hydrometeorological conditions (mainly low precipitation compared to other regions in France), the development of small farm dams in north-western France would result in greater decreases in river flows and less efficient filling of small farm dams than in other regions. Therefore, such dams might not be as efficient as expected in supplying water to farmers when needed. Moreover, the ability to fill small farm dams is projected to decrease in a context of climate change, despite the uncertainty on the evolution of precipitation, thus worsening the situation.
Temperature distribution and Hadley circulation in an axisymmetric model
Authors: Tartaglione N.
Published: November 2014

Abstract. The impact of the temperature distribution on the Hadley circulation simulated by an axisymmetric model is studied. The temperature distributions that drive the model are modulated here by two parameters, n and k, the former controlling the horizontal broadness and the latter defining change in the vertical lapse rate. In the present study, the changes of the temperature distribution mimic changes of the energy input of the atmospheric system leaving as an invariant the equator-poles difference. Both equinoctial and time-dependent Hadley circulations are simulated and results compared. The results give evidence that concentrated temperature distributions enhance the meridional circulation and jet wind speed intensities even with a lower energy input. The meridional circulation and the subtropical jet stream widths are controlled by the broadness of horizontal temperature rather than the vertical lapse rate k, which is important only when the temperature distribution is concentrated at the equator. The jet stream position does not show any dependence with n and k, except when the temperature distribution is very wide and in such a case the jet is located at the mid-latitude. Using n = 2 and k = 1 we have the formulation of the potential temperature adopted in classical literature. A comparison with other works is performed and our results show that the model running in different configurations (equinoctial, solstitial and time-dependent) yields results similar to one another.
Do wild titi monkeys show empathy?
Authors: Clyvia A. , Kaizer M. C. , Santos R. V. , Young R. J. , Cäsar C.
Published: October 2014

Abstract. We observed a putative case of empathy among wild black-fronted titi monkeys (Callicebus nigrifrons) from two different groups (D and R). In over 10 years of behavioural observations of five habituated groups of this species, only low levels of inter-group tolerance have been observed. However, on one day, we encountered the adult male from group D limping (poor hind limb motor coordination) as he travelled alone along the ground. Interestingly, we observed that members of group R did not express any agonistic behaviour towards this neighbouring male and apparently allowed this disabled individual to follow them in the forest for over 5 h. They stayed low in the forest (< 2 m above the ground) and < 10 m horizontally from the individual, and remained in visual contact with him. At the end of the day, this male from group D slept in the sleeping site of group R and was groomed by the adult female of group R. Such tolerance between members of different groups has never been previously observed in this species. Furthermore, group R exposed themselves to increased predation risk by staying close to the ground for protracted periods. The behaviour of group R could be interpreted by as a putative case of empathic responding in this species.
Algunas cuestiones de interés sobre el Derecho Español protector de los consumidores y usuarios
Authors: Peñas Moyano Benjamín
Published: October 2014

DOI: http://dx.doi.org/10.5377/derecho.v0i10.1535
Jurisprudencia Laboral
Authors: Malespín Martínez Fernando
Published: October 2014

DOI: http://dx.doi.org/10.5377/derecho.v0i7.1532
King Hu’s Cinema Opera in his Early Wuxia Films
Authors: Law Ho-Chak
Published: October 2014

Abstract. Widely regarded as a seminal work that redefined wuxia film, King Hu’s debut Come Drink With Me (1966) demonstrates a distinctive appropriation of Peking opera. This paper investigates Hu’s unique creation of cinema opera, focusing on the use of music and Chinese operatic expressions in his early wuxia films.
Effect of the practices of forest establishment on the soil organic carbon and soil aggregate stability in the North-East of Argentina
Authors: Lupi A. M. , Conti M. , Fernandez R. , Consentino D. , López G.
Published: October 2014

This study evaluated the behaviour of organic carbon, labile carbon and aggregate stability under different residue management systems after harvesting of Pinus elliottii E. at the beginning of the second rotation. After 3 years and 5 month of applied the treatment was compared the following systems of site preparation: 1) extraction of forest residues, 2) burning and tillage, and 3) conservation of residues on the soil. The extraction of residues, and burns with disk caused a fall in the organic carbon soil OC of the 20% and 37% in the 0-5 cm and 5-15 cm layer. The loss of light carbon was of the 35% in surface and of the 50% in subsurface. The aggregate mean weight diameter wet sieving was affected by residue extraction. The smaller aggregates were found following the application of burning and tillage practices. The change in aggregate diameter indicated a marked process of loss of the structure associated with the decrease of the organic carbon and with the light carbon to apply intensive practices of site.
Absence of ecotypic differentiation in Mediterranean stone pine in a Spanish inland region
Authors: Gordo Alonso J. , Mutke Regneri S. , Gil Sánchez L.
Published: October 2014

The relicts of stone pine forests on marly or even gypsiferous slopes with high pH values induced the hypothesis of a possible genetic adaptation to this site types, marginal for a species normally growing on siliceous sandy plains. Actually, the forest reproductive materials from selected seed stands on those slopes are used preferably for forestations on analogous sites. In 1998, a multi-site comparative test was established with plant lots obtained from seven selected seed stands and two non-selected seed sources. At least up to the age of eight years, the saplings did not show any significant differentiation among basic materials in outplanting success, survival, vegetative phase change, height or diameter growth, whereas a common, strong phenotypic plasticity among test sites was observed. Hence there seems to be no reason for managing separately seed lots and plants of the same provenance and certify category (e.g. selected reproductive material) instead of mixing them.
Populus genus for the biomass production for energy use: a review
Authors: Sixto H. , Hernandez M. J. , Barrio M. , Carrasco J. , Cañellas I.
Published: October 2014

Much attention is currently focused on biomass production as one possible alternative energy source because of the need to increase the amount of energy produced in Spain from renewable energy sources. Amongst the different types of biomass available, those crops which are specifically designed for the purpose, the so-called «energy crops», allow us not only to plan the production of this resource but also to provide a viable alternative for agricultural land in areas where traditional crops are gradually being abandoned. The objective of this study is to revise the current knowledge base in relation to Populus spp.; a woody crop with great potential for this purpose which can be grown at high densities in short rotation coppices. Its suitability for the production of energy producing biomass will be assessed, focusing in particular on the base material to be employed, the plantation design and the cultural treatments to be applied.
Short communication. Flowering induction by GA4/7 application and mineral fertilization in a Pinus radiata D. Don seed orchard in Sergude (Galicia)
Authors: Codesido V. , Merlo E.
Published: October 2014

Application of gibberellins GA4/7 was an efficient method of promoting female strobilus production in a three year old clonal radiata pine seed orchard in northern Spain. Four clones were selected including one poor flowering clone, one intermediate flowering clone and two good flowering clones, according to this annual flower account (2000). The gibberellins were applied in July and in August (2000) by stem injection of an ethanolic solution of GA4/7. There were no differences in the effectiveness of application on the different dates. Gibberellins produced an increase in the mean number of female cones, that was more effective in poor flowering clones, and a significant decrease in the percentage of empty seeds in poor and intermediate flowering clones in the next harvests. The seed orchard was divided into three zones according to the slope, and was fertilized with NPK 15-5-20 at one of three times (May, June or July 2000) for promoting male flowering in the seed orchard. Regardless of time of application, fertilization resulted in a 3-fold increase in the mean number of male cones produced, without female production effect.
Optimising the management of Pinus nigra Arn. stands under endogenous risk of fire in Catalonia
Authors: González-Olabarria J. R. , Palahí M. , Pukkala T. , Trasobares A.
Published: October 2014

The present study considers the risk of fire as an endogenous component in a stand management optimisation problem for even-aged Pinus nigra Arn. stands in Catalonia (North-east Spain). A simulation-optimisation system, RODAL, was used to determine the optimal stand management when maximal soil expectation value (SEV) was the objective. This system was modified to include fire occurrence and post-fire tree survival models. The fire occurrence and post-fire survival models used in the study have been developed for forest planning purposes using explanatory variables that relate the probability of fire occurrence and the expected loss to such stand variables which can be affected by management actions. Non-linear stochastic optimisation was used to find the optimal stand management schedule. The rotation length as well as the timing and intensity of thinnings were optimised. The inclusion of the risk of fire had a clear effect on the optimal stand management schedule, especially on the regime of thinnings which tended to include early thinnings as means of reducing the risk and expected loss. The regeneration cuts tended to be earlierwith increasing fire risk.
Influence of overstory density on understory light, soil moisture, and survival of two underplanted oak species in a Mediterranean montane Scots pine forest
Authors: Rodríguez-Calcerrada J. , Mutke S. , Alonso J. , Gil L. , Pardos J.A. , Aranda I.
Published: October 2014

Information of tree-nurse shelterwood effects on survival of underplanted seedlings is particularly scant in Mediterranean forest ecosystems. To study light and water resources availability and survival associated to overstory density, two-year-old seedlings of Quercus petraea (Matt.) Liebl. (sessile oak) and Quercus pyrenaica Willd. (pyrenean oak) were planted in the understory of an even-aged Scots pine (Pinus sylvestris L.) plantation located in central Spain, which had been previously assigned to three density treatments: uncut, 33% thinned and 50% thinned of the original density, each replicated four times. Soil moisture was measured with a TDR during the first growing season after planting. Light conditions were estimated by hemispherical photography. Survival was measured at the end of the first growing season in the field and at the beginning of the next two growing seasons. The reduction in density after thinning had a positive effect on light availability and on near-surface soil moisture. Pyrenean oak had higher survival rates than sessile oak, which showed similarly high mortality rates in all three overstory treatments. Thinning had a positive effect on the survival of pyrenean oak, though irrespective of the intensity. Overall, these results point to the necessity to reduce canopy tree density in Mediterranean mountain pinewoods before carrying out enrichment plantations beneath.
Payment for environmental services between the adding and the subsidization: application to the valuation of the landscape in the San Juan dam, Madrid, Spain
Authors: Flores Velásquez P. , Martínez de Anguita P. , Romero Calcerrada R. , Novillo C. J. , Ruiz M. A.
Published: October 2014

A payment for environmental services (PES) based on the beauty of the San Juan dam landscape is proposed containing two innovative aspect in regard to previous PES systems: the elaboration of a diagnosis oriented to obtain a shared vision of the area based in a participative process including all relevant local stakeholders, and the integration of the PES mechanism into the regional public environmental policy. The proposed system also identifies the offer and the demand of the environmental service. It shows the main problems associated to the preservation of the service and proposes management plans oriented to its conservation. Finally, the economic viability of the system is studied comparing three different scenarios according to the grade of integration of the PES model into the regional conservation public policy. This paper shows how a PES system can be used to guarantee public investments in nature conservation through a private management.
The relative dependence of Spanish landscape pattern on environmental and geographical variables over time
Authors: Ortega M. , Bunce R. G.H. , García del Barrio J. M. , Elena-Rossello R.
Published: October 2014

The analysis of the dependence of landscape patterns on environment was carried out in order to investigate the landscape structure evolution of Spain. The underlying concept was that the dependence between landscape spatial structure and environmental factors could be gradually decreasing over time. Land cover data were recorded from aerial photo interpretation of 206 4 × 4 km2 samples from three different years: 1956, 1984 and 1998. Geographical variables were taken into consideration together with the purely environmental ones. General Linear Models of repeated measures were then used to segregate environmental from geographical effects on the pattern of the land cover patches of the samples. Aridity, lithology and topography were the environmental factors used to analyse structural indices of landscape. Landscape composition has a higher dependence on environment than configuration. Environmental variables showed higher correlations with landscape composition and configuration than geographical variables. Among them, overall the climatic aridity and topography significantly accounted for more variation than did lithology. There was a high degree of stability in land cover composition over time, with some significant exceptions. Nevertheless, the registered increase of fragmentation over time has demonstrated that configuration measures are needed to fully assess landscape change.
Forested landscapes dynamics in relation to forest fire occurrence in peninsular Spain: 1987-2000
Authors: Vázquez de la Cueva A. , Rodriguez-Martin J. A.
Published: October 2014

Forest fires play a determinant role in landscape configuration, that is, the type and the spatial distribution of major land cover types in large areas of Spain. One possible way to evaluate this role is by means of the comparison between the area affected by forest fires and changes in land cover types during a certain type period. Based on the importance of wildland fires during the last decades in Spain it is expected a strong relationship between landscape changes and fire occurrence. In order to validate this hypothesis we have analysed the relationship between the changes in land cover types identified in the two land cover classifications carried out until now in the European programme CORINE Land Cover (CLC) and fire occurrence in peninsular Spain for a similar time period. The analyses are based on non parametric correlations and in a canonical ordination analysis between several fire variables and the different types of land cover change in which the dynamic of forested landscapes has been resumed according to the two land cover classification used: CLC-1990 and CLC-2000. The territorial units used are the division of Spain in agrarian counties and the reference period the 14 years spanned between the satellite images used in each classification. Focussing of the forested area, the more important changes detected are the changes from woodland to non-woodland (21%), from non-woodland to woodland (23%) and changes between the different types of land-cover included in the non-woodland class (22%). These three types of changes, that accounted for a 66% of changes in forested areas, have been the more related to fire occurrence. The results show a strong relation between both processes. We have obtained statistically significant results in the correlation and also in the multivariate redundancy analyses. These results confirm the determinant role that fires have played, and certainly will play, in the vegetation dynamic of regions each time more prone to fire such as peninsular Spain.
Silvicultural characterization of the Cantabrian beech forest: the influence of site conditions and anthropic uses
Authors: Gómez-Manzanedo M. , Roig S. , Reque J. A.
Published: October 2014

The goal of this study is the description of different structures within the Cantabrian beech forests, and the assessment of the influence in the stand structure of factors of ecological site and human use. As a first approach, a typological classification of the Cantabrian beech forests was established. Based on this classification the relation between forest structure and previously established ecological classifications was analysed: regions of provenance, territorial areas and potential areas derived from population ecology studies. The data base for the establishment of the typological classification was the Third National Forest Inventory. The multivariate analysis of the IFN3 plots with beech as dominant species in the Cantabrian range allowed us to define seven beech forest structure types. The main difference between groups was stand density, diametric distribution and species diversity. Finally we compared the stand types obtained with the different ecological and administrative classifications. Beech forests in the southern Cantabrian range presented more pole stages while the presence of timber stages was more important in the northern part of the Cantabrian range. The results show that structural heterogeneity in the beech forest is determined by the union of ecological and anthropic factors.
Floristic changes induced by fire on Pinus sylvestris plantations in northwest of Spain
Authors: Nuñez M. R. , Calvo L. , Pando V. , Bravo F.
Published: October 2014

The effects of wildfire on vegetation regeneration in the understory of stands dominated by Pinus sylvestris L. in north-west Spain were analysed. In order to study changes in the composition of this community, three study areas dominated by Pinus sylvestris L. and burned by a summer wildfire were selected. In each area three permanent plots of 25 × 1 m2 was established. The cover percentage of plant species present, and the cover of life forms and richness were analysed yearly from the first to the fourth year after fire. Total cover values generally increased throughout the study period. The species that appeared during the first years were those that would dominate in the mature stage, such as Erica australis L. and Pterospartum tridentatum (L.) Willk, both species being typical resprouters. Other species that appeared from the first year are typical seeders like Pinus sylvestris L. and Halimium alyssoides (Lam.) K. Koch. Floristic richness values showed higher values during the first year after fire than in the original situation, due to the fast recovery of the herbaceous species in the open spaces created by fire. After the first year changes in richness values were not significant
A sampling method for estimating sporocarps production of wild edible mushrooms of social and economic interest
Authors: Ortega-Martínez P. , Martínez-Peña F.
Published: October 2014

This study introduces a new approach to determine and assess total mushroom production as well as to partitioning off this gross production into: non-harvested unripe production; non-harvested ripe production; harvested production; production eaten by fauna; and damaged production. Nine 300 m-long transects were established in the studied area. The sampling method was carried out in 2004, 2005 and 2006, but 2006 was the most productive year. In this year, a production of 5.37 kg/ha was estimated for Boletus edulis in 2006 of which 24% of Boletus edulis gross production was harvested, 26% was damaged and 15% was recorded as ripe production. The distribution of the gross production by classes permits knowing essential aspects regarding edible mushrooms management including which pressure is undergoing the fungal resource (due to harvesting or grazing), quantity and quality of the production or whether the species regeneration is guaranteed at any momenThis information allows us to ascertain the fungal resources conservation state and undertake a management and regulatory process for edible mushrooms in the sampled areas.
Site, hybrid crosses and clone effect on growth and wood properties of Populus
Authors: Monteoliva S. , Senisterra G.
Published: October 2014

The objective of this paper was to study site, hybrid cross and clone effects on total height, BHD [Breast height diameter], volume, wood basic density, fibre length and yield, of eleven poplars clones. 10-year-old hybrid poplar clones were sampled at two sites in Argentina (MD and EG). The material studied consisted of two poplar hybrid crosses Populus deltoides x P. deltoides and P. deltoides x P. nigra (P. x canadensis = P. x euramericana), as well as P. deltoides. Sites influenced significantly growth traits and wood density, hybrid influenced tree height, wood density and fibre length and clones influenced all variables. MD trees were 5% higher and 2% denser than EG trees, but EG trees were 7% greater in BDH and 11% more volume than the MD trees. P. deltoides and P. deltoides intra specific crosses were 4% higher and 4% denser than P. x canadensis trees. P. x canadensis fibre length was 3% higher than P. x deltoides. According to all properties, difference between site and hybrid were not very importanThe properties of the clones had different responses regardless of the hybrid crosses. 610-31 and 564-17 clones (P. x deltoides) and 568-1 and Triplo (P. x canadensis) clones were distinguished.
Technical innovation in Spain's forestry industry
Authors: Voces González R. , Herruzo A. Casimiro , Díaz-Balteiro L.
Published: October 2014

This paper intends to provide an overview of the technological innovation in the Spanish wood-based industry. This characterization will be carried out through the analysis of a set of indicators based on both secondary and primary data, the later obtained from a survey taken in 2007. Results indicate a weakness and backwardness in the innovation activities performed in the forest industry, with respect to the overall Spanish manufacturing industry. This gap is wider in the case of R&D activities. However, it is necessary to indicate that the important limitations observed in the way firms carry out their innovation activities, are shared with the overall traditional manufacturing sectors.
Understanding knowledge sharing between judges
Authors: Taal Sandra
Published: November 2014

Understanding knowledge sharing between judges A quantitative analysis

Over the last two decades, there has been a growing interest in the development and implementation of knowledge management systems. In the judicial context, these knowledge management systems are designed to support judges in the decision-making process by providing them with the knowledge that they need in order to deal with doubts or uncertainties in complex cases. However, less attention has been given to the related process of knowledge sharing between judges. In order to optimally benefit from the knowledge available in the organization, this process should be better understood and acted upon. The aim of this research project is to gain a better insight into the interactive process of knowledge sharing between judges. To this end, a research model has been developed which will be quantitatively tested on the basis of survey responses from judges.
Ervaringen uit de collegezaal
Authors: Baas Reyer
Published: November 2014

Experiences from the lecture-room

When Dutch-speaking sociologists of law meet, actual research is heavily discussed. Education, unfortunately, is rarely a topic of discussion. In 2014 sociologists of law gathered to exchange experiences in and ideas on education. This article gives an account of the discussion.

The sociologists of law proved to be united on a number of fundamental questions. They concluded that it is useful to have students do research and to connect education in sociology of law with legal courses. This helps in realizing the ultimate goal: to have students achieve a greater understanding of the law by means of socio-legal insights. However, opinions diverged on the question of whether present educational practices in sociology of law are sufficiently renewing and attractive to students. Keep on reading to find out about other educational perspectives, challenges and solutions.
Weet wat je tweet
Authors: Roodenburg Dick , Boutellier Hans
Published: November 2014

Knowing how to use Twitter. How Twitter can contribute to confidence in the police

Community policing is a common strategy in the Dutch police organization: working in a geographically bounded area, in close proximity and engagement with the local population. The use of Twitter by local police-officers is an increasingly popular way of communicating in this context. Prior research has indicated that there is a positive relation between the use of Twitter by the local police officer and citizens’ confidence in the police. But what factors determine this confidence and how can it be strengthened by using Twitter? This article examines the nature of police tweets and shows how tweets can contribute to improving the degree of confidence between citizens and the police. To determine what factors influence confidence we made use of the model of trust and confidence by Jackson and Bradford. This model differentiates between ‘effectiveness’, ‘fairness’, and ‘engagement’. These three factors are used to explore the way tweets might influence confidence in policing. The empirical research included interviews with three police officers who twitter actively, as well as interviews with 30 ‘followers’ living in the neighbourhood where the police officer works. Also an analyses has been carried out of the tweets made by the police officers in one year, 3.506 tweets in total, by categorizing the tweets according to the model of Jackson and Bradford. We conclude that the model of Jackson and Bradford is useful to explore the possible relationship between the use of Twitter and citizens confidence in the police. Using Twitter by the local police officers seems to make a possible contribution to the degree of confidence in the police. Our categorization of Twittermessages allowed us to give practical recommendations to local police officers how to use Twitter in order to improve confidence among citizens. The data also suggest that followers appreciate the fact that local police officers show their knowledge of current affairs in the neighbourhood.
Loss to follow‐up of HIV‐infected women after delivery: The Swiss HIV Cohort Study and the Swiss Mother and Child HIV Cohort Study
Authors: Aebi‐Popp Karoline , Kouyos Roger , Bertisch Barbara , Staehelin Cornelia , Hoesli Irene , Rickenbach Martin , Thorne Claire , Grawe Claudia , Bernasconi Enos , Cavassini Matthias , Martinez de Tejada Begona , Stoeckle Marcel , Lecompte Thanh , Rudin Christoph , Fehr Jan
Published: November 2014

Introduction

HIV‐infected pregnant women are very likely to engage in HIV medical care to prevent transmission of HIV to their newborn. After delivery, however, childcare and competing commitments might lead to disengagement from HIV care. The aim of this study was to quantify loss to follow‐up (LTFU) from HIV care after delivery and to identify risk factors for LTFU.

Methods

We used data on 719 pregnancies within the Swiss HIV Cohort Study from 1996 to 2012 and with information on follow‐up visits available. Two LTFU events were defined: no clinical visit for >180 days and no visit for >360 days in the year after delivery. Logistic regression analysis was used to identify risk factors for a LTFU event after delivery.

Results

Median maternal age at delivery was 32 years (IQR 28–36), 357 (49%) women were black, 280 (39%) white, 56 (8%) Asian and 4% other ethnicities. One hundred and seven (15%) women reported any history of IDU. The majority (524, 73%) of women received their HIV diagnosis before pregnancy, most of those (413, 79%) had lived with diagnosed HIV longer than three years and two‐thirds (342, 65%) were already on antiretroviral therapy (ART) at time of conception. Of the 181 women diagnosed during pregnancy by a screening test, 80 (44%) were diagnosed in the first trimester, 67 (37%) in the second and 34 (19%) in the third trimester. Of 357 (69%) women who had been seen in HIV medical care during three months before conception, 93% achieved an undetectable HIV viral load (VL) at delivery. Of 62 (12%) women with the last medical visit more than six months before conception, only 72% achieved an undetectable VL (p=0.001). Overall, 247 (34%) women were LTFU over 180 days in the year after delivery and 86 (12%) women were LTFU over 360 days with 43 (50%) of those women returning. Being LTFU for 180 days was significantly associated with history of intravenous drug use (aOR 1.73, 95% CI 1.09–2.77, p=0.021) and not achieving an undetectable VL at delivery (aOR 1.79, 95% CI 1.03–3.11, p=0.040) after adjusting for maternal age, ethnicity, time of HIV diagnosis and being on ART at conception.

Conclusions

Women with a history of IDU and women with a detectable VL at delivery were more likely to be LTFU after delivery. This is of concern regarding their own health, as well as risk for sexual partners and subsequent pregnancies. Further strategies should be developed to enhance retention in medical care beyond pregnancy.
Closing in on a mechanism for activation
Authors: Hubbard Stevan R , Miller W Todd
Published: October 2014

When insulin-like growth factor-1 (IGF1) binds to its receptor, a physical constraint is released that allows the two transmembrane helices to come together to facilitate activation of the receptor.
Lifting the lid on pilus assembly
Authors: Remaut Han , Ben-Tal Nir
Published: October 2014

A combination of computer simulations, evolutionary analysis and graph theory has provided new insights into the assembly of pili on the surface of bacteria.
Better Data to Improve Medicaid
Authors: Allen Heidi , Baicker Katherine
Published: August 2024

This JAMA Forum discusses the current data collection mechanisms used for Medicare and proposes ways to improve nationwide data collection efforts for Medicaid.
Changes in Secure Messaging After Implementation of Billing E-Visits by Demographic Group
Authors: Holmgren A. Jay , Grouse Carrie K. , Oates Aris , O’Brien Julie , Byron Maria E.
Published: August 2024

This cohort study investigates the association of demographic characteristics with changes in patient portal messaging after implementation of e-visit billing.
Cold Capping—A Medical Student’s Perspective As a Caregiver
Authors: Evans Fiona
Published: August 2024

This essay describes a medical student’s experience caring for her sister with breast cancer.
Cannabis Use and Head and Neck Cancer
Authors: Gallagher Tyler J. , Chung Ryan S. , Lin Matthew E. , Kim Ian , Kokot Niels C.
Published: August 2024

Importance

Cannabis is the most commonly used illicit substance worldwide. Whether cannabis use is associated with head and neck cancer (HNC) is unclear.

Objective

To assess the clinical association between cannabis use and HNC.

Design, Setting, and Participants

This large multicenter cohort study used clinical records from a database that included 20 years of data (through April 2024) from 64 health care organizations. A database was searched for medical records for US adults with and without cannabis-related disorder who had recorded outpatient hospital clinic visits and no prior history of HNC. Propensity score matching was performed for demographic characteristics, alcohol-related disorders, and tobacco use. Subsequently, relative risks (RRs) were calculated to explore risk of HNC, including HNC subsites. This analysis was repeated among those younger than 60 years and 60 years or older.

Exposure

Cannabis-related disorder.

Main Outcomes and Measures

Diagnosis of HNC and any HNC subsite.

Results

The cannabis-related disorder cohort included 116 076 individuals (51 646 women [44.5%]) with a mean (SD) age of 46.4 (16.8) years. The non–cannabis-related disorder cohort included 3 985 286 individuals (2 173 684 women [54.5%]) with a mean (SD) age of 60.8 (20.6) years. The rate of new HNC diagnosis in all sites was higher in the cannabis-related disorder cohort. After matching (n = 115 865 per group), patients with cannabis-related disorder had a higher risk of any HNC (RR, 3.49; 95% CI, 2.78-4.39) than those without cannabis-related disorder. A site-specific analysis yielded that those with cannabis-related disorder had a higher risk of oral (RR, 2.51; 95% CI, 1.81-3.47), oropharyngeal (RR, 4.90; 95% CI, 2.99-8.02), and laryngeal (RR, 8.39; 95% CI, 4.72-14.90) cancer. Results were consistent when stratifying by older and younger age group.

Conclusions and Relevance

This cohort study highlights an association between cannabis-related disorder and the development of HNC in adult patients. Given the limitations of the database, future research should examine the mechanism of this association and analyze dose response with strong controls to further support evidence of cannabis use as a risk factor for HNCs.
PDL1/HER2‐Targeted Lipid‐Encapsulated Oxygen Nanobubbles Combined with Photodynamic Therapy for HER2+ Breast Cancer Immunotherapy
Authors: Tian Jilai , Wan Shixiao , Yang Zhen , Wang Mengting , Zhou Wenzhao , Wo Guanqun , Fu Shuping , Zheng Shiya , Zhou Gaoxin , Hu Xiaomin , Guo Yichen , Guo Jun
Published: August 2024

Programmed death (PD) 1/PD ligand 1 (PDL1) inhibitors are immune checkpoint inhibitors (ICIs) that may facilitate HER2‐positive breast cancer treatment; however, their clinical efficacy remains elusive. Oxygen‐enhanced photodynamic therapy (PDT) increases immunogenic cell death (ICD), providing a promising strategy to render the tumor microenvironment more sensitive to the ICIs. Lipid‐encapsulated oxygen nanobubbles (Lipo‐NBs‐O2) obtained using nanobubbles (NBs) water for oxygen delivery in vivo can facilitate enhanced PDT. Here, dual‐receptor targeted Lipo‐NBs‐O2 (DRT@Lipo‐NBs‐O2) is prepared by modifying Lipo‐NBs‐O2 with anti‐PDL1 scFv and the fusion protein anti‐HER2 scFv‐tandem‐repeat cytochrome c (anti‐HER2‐nCytc). Copper phthalocyanine is the photosensitizer (PS). DRT@Lipo‐PS‐NBs‐O2 plus near‐infrared irradiation leads to robust ICD induction, increasing DC activation and CD8+ T‐cell numbers. Modification with anti‐PDL1 scFv improves tumor distribution of DRT@Lipo‐PS‐NBs‐O2 and plays the ICI role, invigorating CD8+ T cells and boosting the effects of immunotherapy. Oxygen supplied through DRT@Lipo‐PS‐NBs‐O2 reduces P‐glycoprotein expression. Enhanced PDT and Cytc can cause tumor cell death, thereby reducing the immune burden. Under dual receptor targeting and laser local irradiation, tumor cells become subject to the combination effects of PDT, ICD, ICIs, and apoptosis; this effectively suppresses tumor growth and metastasis. Lipo‐NBs‐O2 affords a combination of oxygen delivery and multidrug therapy to alleviate HER2‐positive breast cancer.
Advancing Insights into Electrochemical Pre‐Treatments of Supported Nanoparticle Electrocatalysts by Combining a Design of Experiments Strategy with In Situ Characterization
Authors: Mule Aniket S. , Tran Kevin , Aleman Ashton M. , Cornejo‐Carrillo Yamile E. , Kamat Gaurav A. , Stevens Michaela Burke , Jaramillo Thomas F.
Published: August 2024

Activation, break‐in, and/or pre‐treatment protocols are generally applied to energy conversion devices before regular operation to reach stable performance. There remains much to understand about the relationships among physical properties, performance, and electrochemical pre‐treatments. Here, a design‐of‐experiments (DoE) strategy is employed to address this gap by demonstrating the influence of five pre‐treatment parameters for carbon‐supported Pt‐nanoparticle catalysts on the electrocatalytic oxygen reduction reaction (ORR). A subset of pre‐treatments, developed using a central composite design, are tested in a flow cell combined with an inductively‐coupled plasma mass spectrometer (on‐line ICP‐MS). The DoE‐based approach facilitates comprehensive insights from two orders of magnitude fewer experiments than a conventional grid search. The coupled on‐line ICP‐MS setup enables effective catalysis and real‐time catalyst dissolution data. Leveraging insights from DoE for on‐line ICP‐MS and additional characterization, a model is built between the degradation of a multi‐dimensional supported Pt surface, its performance, and applied electrochemical parameters. These investigations identify surface modifications, such as oxidation, and subsequent restructuring of Pt during pre‐treatment as a primary cause of performance deterioration during ORR. By combining DoE with advanced characterization techniques, a powerful approach is demonstrated to gain a mechanistic understanding of pre‐treatment protocols that can be broadly adapted to various reaction chemistries.
Sea trout (Salmo trutta) activity and movement patterns in response to environmental cues in a fjord system
Authors: Staveley Thomas A. B. , van der Meijs Felix , Gullström Martin
Published: August 2024

As a predatory fish that migrates between freshwater and marine environments, the sea trout (Salmo trutta) is important in linking these systems. This study investigated movement patterns of sea trout in a coastal fjord at the Swedish Skagerrak region from August 2018 to January 2019, using acoustic telemetry, while assessing these against environmental variables across different spatial and temporal scales. Six acoustic receivers were deployed in the fjord and a river, which flows into the upper reaches of the fjord, with the aim of detecting 20 sea trout that had been tagged with acoustic transmitters. Sea surface temperature and winds (east–west) affected movement patterns of the sea trout the most, while changes in atmospheric pressure were also important, but to a lesser extent. Sea surface temperature and atmospheric pressure both had a positive relationship with the number of detections, whereas stronger winds from the east (i.e. from land) resulted in more detections than stronger winds from the west (i.e. from the ocean). In addition, interesting diel (day–night) movement patterns were observed for some fish. A significant positive correlation was also discovered between the weight of the fish and the number of detections. This study offers insight in movements of sea trout that use coastal habitats and how environmental conditions can affect movement patterns in a fjord system. To further our understanding of sea trout movement patterns and connectivity, tracking from river, through fjord, out to sea and at a longer time scale with more variation in fish size would be valuable to understand more about the complex movement dynamics of this important species.
Divergent lineages in a young species: The case of datilillo (Yucca valida), a broadly distributed plant from the Baja California Peninsula
Authors: Aleman Alberto , Arteaga Maria Clara , Gasca‐Pineda Jaime , Bello‐Bedoy Rafael
Published: August 2024

Premise

Globally, barriers triggered by climatic changes have caused habitat fragmentation and population allopatric divergence. Across North America, oscillations during the Quaternary have played important roles in the distribution of wildlife. Notably, diverse plant species from the Baja California Peninsula in western North America, isolated during the Pleistocene glacial–interglacial cycles, exhibit strong genetic structure and highly concordant divergent lineages across their ranges. A representative plant genus of the peninsula is Yucca, with Y. valida having the widest range. Although a dominant species, it has an extensive distribution discontinuity between 26° N and 27° N, suggesting restricted gene flow. Moreover, historical distribution models indicate the absence of an area with suitable conditions for the species during the Last Interglacial, making it an interesting model for studying genetic divergence.

Methods

We assembled 4411 SNPs from 147 plants of Y. valida throughout its range to examine its phylogeography to identify the number of genetic lineages, quantify their genetic differentiation, reconstruct their demographic history and estimate the age of the species.

Results

Three allopatric lineages were identified based on the SNPs. Our analyses support that genetic drift is the driver of genetic differentiation among these lineages. We estimated an age of less than 1 million years for the common ancestor of Y. valida and its sister species.

Conclusions

Habitat fragmentation caused by climatic changes, low dispersal, and an extensive geographical range gap acted as cumulative mechanisms leading to allopatric divergence in Y. valida.
Die Click‐to‐Release‐Aktivierung des Reserveantibiotikums Colistin am Zielort verringert dessen Nierentoxizität
Authors: Charoenpattarapreeda Jiraborrirak , Tegge Werner , Xu Chunfa , Harmrolfs Kirsten , Hinkelmann Bettina , Wullenkord Hannah , Hotop Sven‐Kevin , Beutling Ulrike , Rox Katharina , Brönstrup Mark
Published: August 2024

Der Einsatz hochwirksamer, aber zugleich toxischer Antibiotika wie Colistin ist aufgrund der Zunahme antimikrobieller Resistenzen unvermeidlich geworden. Wir berichten hier, wie geschütztes Colistin chemisch am Ort der Infektion kontrolliert mithilfe von click‐to‐release‐Reaktionen freigesetzt werden kann, um seine systemische Toxizität zu verringern. Kinetische Experimente mit neun Tetrazinen und drei Dienophilen zeigten eine besonders schnelle Wirkstoff‐Freisetzung über eine Diels–Alder‐Reaktion mit inversem Elektronenbedarf zwischen einem trans‐Cycloocten (TCO) und dem aminfunktionalisierten Tetrazin Tz7. Die antibiotische Aktivität von Colistin gegen Escherichia coli wurde durch TCO‐Einheiten maskiert, aber durch die Reaktion mit d‐Ubi−Tz, einem Tetrazin, das mit dem an Bakterien bindenden Peptid D‐Ubi29–41 funktionalisiert ist, wiederhergestellt. Während neutral geladenes TCO die Toxizität gegenüber der humanen proximalen Tubulus‐Nierenzelllinie HK‐2 nicht verbesserte, verringerte mit Asparaginsäure modifiziertes TCO die Gesamtladung des Peptids und den Eintritt in die Nierenzellen, wodurch seine Toxizität drastisch verringert wurde. Das Analogon Col−(TCO‐Asp)1 zeigte bei Mäusen günstige pharmakokinetische Eigenschaften und wurde in einem in vivo Infektionsmodell durch d‐Ubi−Tz lokal in der Lunge aktiviert, während es ohne den chemischen Auslöser inaktiv blieb. Diese Studie liefert das erste Beispiel für ein systemisch wirkendes Zweikomponenten‐Antibiotikum mit verbesserter Arzneimittelverträglichkeit.
Highly Selective Production of C2+ Oxygenates from CO2 in Strongly Acidic Condition by Rough Ag‐Cu Electrocatalyst
Authors: Yang Yisen , Zhang Jianling , Tan Zhonghao , Yang Jie , Wang Sha , Li Meiling , Su Zhuizhui
Published: August 2024

The acidic electrocatalytic conversion of CO2 to multi‐carbon (C2+) oxygenates is of great importance in view of enhancing carbon utilization efficiency and generating products with high energy densities, but suffering from low selectivity and activity. Herein, we synthesized Ag−Cu alloy catalyst with highly rough surface, by which the selectivity to C2+ oxygenates can be greatly improved. In a strongly acidic condition (pH=0.75), the maximum C2+ products Faradaic efficiency (FE) and C2+ oxygenates FE reach 80.4 % and 56.5 % at −1.9 V versus reversible hydrogen electrode, respectively, with a ratio of FEC2+ oxygenates to FEethylene up to 2.36. At this condition, the C2+ oxygenates partial current density is as high as 480 mA cm−2. The in situ spectra, control experiments and theoretical calculations indicate that the high generation of C2+ oxygenates over the catalyst originates from its large surface roughness and Ag alloying.