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An electro-optic birefringence technique was employed to study the orientation mechanism of montmorillonite in an electric field. The instantaneous reversal of the field polarity produced evidence of a low voltage permanent dipole and a high voltage induced dipole. This technique was used to study theeffect ofelectrolyte concentration on the rotational diffusion coefficient, a measure of the rate at which the particles rotate or relax, within the solution, from a preferred orientation. Thus, a measure of the immediate environment of the particles was obtained that is not an average effect for the whole system, yet allows for the full development of the clay-cation-water interactions under the experimental conditions. It was found that particle rotation could be accounted for using the measured particle size and normal water viscosity only when the double layer was fully developed, with no free ions or other perturbations. As soon as perturbations were applied, either by adding salts or applying an electric field, the measured particle size and normal viscosity would not account for the data. Either the rotating moiety has to be larger, that is, be a particle plus a water hull, or the viscosity greater, or in some cases both.
An electrooptic birefringence technique was employed to study the effect of particle size, saturating cation, and clay type on the rotational diffusion coefficient (a measure of the rate at which the particles rotate or relax within the solution) from a preferred orientation. These studies help elucidate the nature of the cation—water environment near the clay particles.
Previous work has shown that some clay particles orient at both low and high voltages due to a permanent dipole and an induced dipole, respectively, whereas other clays under similar short-duration pulses orient only at high voltages. The permanent dipole was attributed to the iron in the octahedral layer of the clay mineral, whereas the induced dipole was probably due to a redistribution of the diffuse double-layer cations. This study shows that smaller clay particles orient more readily at low voltages and have greater rotational diffusion coefficients at high voltages. The higher the rotational diffusion coefficient, the faster the particles move in their surrounding water-cation environment. The effect of the saturating cation on the rotational diffusion coefficients was Na > Li > K for the permanent dipole and K > Li > Na > Ca > Mg for the induced dipole orientation. Previous results (Schepers and Miller, 1974) are interpreted to mean that a particle in dilute suspension can rotate independently of its environment only when the salt concentration in the surrounding medium approaches zero. At higher salt concentrations, or if the particle environment is perturbed by an electric field, the particle rotates with a water shell. As the concentration of salt or strength of the electric field increases further, either the viscosity of the surrounding solution increases or the size of the rotating shell is greatly increased. Thus, the water around clay particles appears to be structurally different than normal, and this condition is probably caused by the nature of the clay—cation interaction.
The nature and timing of the transition to farming north of the Linearbandkeramik zone in Europe is the subject of much debate, but our understanding of this fundamental shift in lifeways is hampered by the low resolution of available data. This article presents new multi-proxy evidence from Swifterbant (4240–4050 BC), in the Dutch wetlands, for morphologically domestic cattle with two different dietary regimes. The authors argue that the results indicate early animal management, alongside arable farming and the continuance of foraging practices, prompting the reconsideration away from broad statements about the Neolithic north of the Linearbandkeramik zone towards more local trajectories.
John T. McGreevy's chronicle of modern Roman Catholic history is a vivid and sometimes jarring reminder of the historical depth of contemporary divisions within the Church, especially as these enter the public sphere. Catholicism: A Global History from the French Revolution to Pope Francis elucidates the church's ambivalent response to the challenge of modernity over the long nineteenth and twentieth centuries, specifically the rise of democratic nation states, anti-colonialist movements from the global south, the struggles of poor and working people for liberation, and feminist and human rights movements. The spread of totalitarianism and the supposed triumph of capitalism represented a different set of challenges for the church in this period.
In this paper, we present empirical research on what we call ‘digital worker feedback infrastructures’ (DWFI); these are communication systems based on digital technologies that allow for creating so-called ‘feedback data’ via different forms of information input of workers in global value chains (GVC). The paper provides an overview of over 50 current DWFIs in GVCs and asks about the main differences between management-oriented and worker-centred digital feedback infrastructures in their usage of worker data. In the first part, we trace the emergence of DWFIs at the intersection of different trends: the continuous non-improvement of working conditions through auditing, the permanent politicisation, and contestation of this fact through labour and activist networks as well as the development of new digital technologies. In the second section, we elaborate the main features of DWFIs and analyse potential shortcomings in the context of the ‘ethical’ audit and monitoring regime for GVCs. Third, we use our dataset to present an overview of the heterogeneity of DWFIs. We pay particular attention to examples of civil society developed tools as we suggest that they provide a glimpse of the potential of worker feedback technologies from below, which could contribute to better monitoring of worker rights and facilitate a more democratic coordination of workplaces and GVCs.
A robust understanding of the impact of anthropogenic activities on high-altitude tropical aquatic ecosystems is key for the conservation and protection of the Tropical Andean biodiversity hot spot. We present the results of a multiproxy study of lake sediments from the high Andean páramo of El Cajas National Park, a UNESCO biosphere reserve in Ecuador. The main site, Laguna Pallcacocha, is well known for recording El Niño–driven clastic flood layers that are triggered by high-intensity rainfall anomalies from the eastern Pacific. The second site, Laguna El Ocho, does not contain clastic laminations, providing a control. The records show abrupt shifts in diatom assemblages ca. AD 1991 in both high-elevation Andean lakes accompanied by local changes in páramo composition that suggest a sudden nutrient enrichment of the environment. The diatom assemblages from Laguna Pallcacocha, in relation to the clastic input events, are remarkably stable and do not show evident El Niño signals at the analysed resolution. Based on comparison with the nonlaminated El Ocho record, we deduce the main source of this nutrient enrichment to be the construction of a heavily transited road that runs through the park, while climate warming played secondary role by amplifying its effects.
Animals have various behavioural and physiological needs that are important for welfare. Fulfilment of these needs depends on the quality of housing, management and animal characteristics. The objective of this study was to develop a model to assign welfare scores to husbandry systems for dairy cattle, based on scientific results, and thereby supporting the design of new, welfare-friendly systems. COWEL is a computer-based decision support system that contains attributes regarding housing and management conditions. These attributes are technical specifications that contain various technical units called levels. These levels are ranked from best-to-worst regarding welfare, based on scientific information about animal-based parameters. This information, inserted in the model as statements, was weighted depending on the impact it has on welfare by using weighting categories. Thereafter, a weighting factor was calculated for each attribute which determines how important an attribute is for welfare. The COWEL model contains 2,343 statements on dairy cattle welfare from 476 sources found during a literature survey. The model was applied to four husbandry systems, namely a tie-stall, cubicle housing, a straw yard and a pasture-based system. The welfare scores, calculated by COWEL for these husbandry systems, correspond with the general opinion about these systems. A tie-stall receives a low and a pasture-based system a high welfare score: 211 and 271, respectively. A husbandry system can receive a maximum of 313 on the welfare scale of COWEL. We conclude that COWEL can be used to rank husbandry systems on a welfare scale, and may be a useful tool to develop new, sustainable and welfare-friendly systems for dairy cattle.
One million pet rabbits are kept in The Netherlands, but there are no data available on their behaviour and welfare. This study seeks to assess the welfare of pet rabbits in Dutch households and is a first step in the development of a welfare assessment system. In an internet survey, housing systems, general up-keep and behaviour of pet rabbits were reported by their owners. The answers of 912 respondents were analysed with behavioural observations carried out on 66 rabbits in as many households. The rabbits were observed in their home cage and during three fear-related tests: a contact test, a handling test and an open-field test. The survey revealed that the average lifespan of the rabbits is approximately 4.2 years (the maximum potential lifespan is 13 years) and solitary housing appears to reduce lifespan. Close to half of respondents subjected their rabbit(s) to solitary housing and the majority housed them in relatively small cages (< 5,000 cm2). Health risks may arise from a failure to inoculate rabbits and via inappropriate diet. During the contact test, solitary-housed rabbits made more contacts with a human than group-housed rabbits and rabbits in a small housing system made more contacts than those in a large system. Observations in the home cage differed greatly compared with the natural time budget of rabbits, ie displaying increased stereotypic behaviour and decreased foraging and, in solitary-housed rabbits, a complete lack of social behaviour. Nearly 25% of rabbits displayed strong resistance to being picked up, indicating socialisation problems. During the open-field test, solitary-housed rabbits sat up more than social-housed rabbits suggesting increased fearfulness. These findings indicate that the conditions in which pet rabbits are kept often have a negative impact on their welfare, further underlining the need to study this in greater detail.
Trauma is the leading cause of death in the Western world. Trauma systems have been paramount in opposing this problem. Commonly, Level 1 Trauma Centers are staffed by in-house (IH) attending trauma surgeons available 24/7, whereas other institutions function on an on-call (OC) basis with defined response times. There is on-going debate about the value of an IH attending trauma surgeon compared to OC trauma surgeons regarding clinical outcome.
Methods:
This study was performed at a tertiary care facility complying with all requirements to be a designated Level 1 Trauma Center as defined by the American College of Surgeons Committee on Trauma (ACSCOT). Inclusion occurred from January 1, 2012 through December 31, 2013. Patients were assigned an identifier for IH trauma surgeon attendance versus OC attendance. The primary outcome variable studied was overall mortality in relation to IH or OC attending trauma surgeons. Additionally, time to operating theater, hospital length-of-stay (HLOS), and intensive care unit (ICU) admittance were investigated.
Results:
A total of 1,287 unique trauma cases in 1,285 patients were presented to the trauma team. Of all cases, 712 (55.3%) occurred between 1700h and 0800h. These 712 cases were treated by an IH attending in 66.3% (n = 472) and an OC attending in 33.7% (n = 240). In the group of patients treated by an IH attending trauma surgeon, the overall mortality rate was 5.5% (n = 26); in the group treated by an OC attending, the overall mortality rate was 4.6% (n = 11; P = .599). Cause of death was traumatic brain injury (TBI) in 57.6%. No significant difference was found in the time between initial presentation at the trauma room and arrival in the operating theater.
Conclusion:
In terms of trauma-related mortality during non-office hours, no benefit was demonstrated through IH trauma surgeons compared to OC trauma surgeons.
Observational studies suggest that hormonal contraceptive use may increase depressive symptoms in women, but it is unclear whether the effect is causal.
Aims
To quantitatively examine the evidence from randomised clinical trials for the link between hormonal contraceptive use and depressive symptoms.
Method
We performed a systematic review and network meta-analysis of randomised clinical trials comparing women randomised to any form of a hormonal contraceptive with women randomised to any other form of a (non-)hormonal contraceptive or placebo. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Web of Science, PsycINFO, EMCare and EMBASE, from inception to 1 May 2020. Certainty of the evidence was assessed with the Grading of Recommendations Assessment, Development and Evaluation approach. A random-effect Bayesian network meta-analysis was conducted, with change in depressive symptoms between baseline and three cycles as outcome.
Results
This review identified 3492 records, of which 14 trials were eligible and 12 could be included in the network meta-analysis. These trials included 5833 participants (mean age per study range: 16.8–32.4 years) and compared 10 different interventions. Compared with placebo, hormonal contraceptive use did not cause worsening of depressive symptoms (standardised mean difference: median, −0.04; range, −0.17 [95% credible interval −0.46 to 0.13] to 0.13 [95% credible interval −0.28 to 0.56]).
Conclusions
This study suggests that hormonal contraceptive use does not lead to an increase in depressive symptoms in adult women. Future studies should include first-time users, to confirm the results in young women.
Arctic mining has a bad reputation because the extractive industry is often responsible for a suite of environmental problems. Yet, few studies explore the gap between untouched tundra and messy megaproject from a historical perspective. Our paper focuses on Advent City as a case study of the emergence of coal mining in Svalbard (Norway) coupled with the onset of mining-related environmental change. After short but intensive human activity (1904–1908), the ecosystem had a century to respond, and we observe a lasting impact on the flora in particular. With interdisciplinary contributions from historical archaeology, archaeozoology, archaeobotany and botany, supplemented by stable isotope analysis, we examine 1) which human activities initially asserted pressure on the Arctic environment, 2) whether the miners at Advent City were “eco-conscious,” for example whether they showed concern for the environment and 3) how the local ecosystem reacted after mine closure and site abandonment. Among the remains of typical mining infrastructure, we prioritised localities that revealed the subtleties of long-term anthropogenic impact. Significant pressure resulted from landscape modifications, the import of non-native animals and plants, hunting and fowling, and the indiscriminate disposal of waste material. Where it was possible to identify individual inhabitants, these shared an economic attitude of waste not, want not, but they did not hold the environment in high regard. Ground clearances, animal dung and waste dumps continue to have an effect after a hundred years. The anthropogenic interference with the fell field led to habitat creation, especially for vascular plants. The vegetation cover and biodiversity were high, but we recorded no exotic or threatened plant species. Impacted localities generally showed a reduction of the natural patchiness of plant communities, and highly eutrophic conditions were unsuitable for liverworts and lichens. Supplementary isotopic analysis of animal bones added data to the marine reservoir offset in Svalbard underlining the far-reaching potential of our multi-proxy approach. We conclude that although damaging human–environment interactions formerly took place at Advent City, these were limited and primarily left the visual impact of the ruins. The fell field is such a dynamic area that the subtle anthropogenic effects on the local tundra may soon be lost. The fauna and flora may not recover to what they were before the miners arrived, but they will continue to respond to new post-industrial circumstances.
Determination of antibodies against ToRCH antigens at the beginning of pregnancy allows assessment of both the maternal immune status and the risks to an adverse pregnancy outcome. Age-standardised seroprevalences were determined in sera from 1009 women of childbearing age residing in Mexico, Brazil, Germany, Poland, Turkey or China using a multiparametric immunoblot containing antigen substrates for antibodies against Toxoplasma gondii, rubella virus, cytomegalovirus (CMV), herpes simplex viruses (HSV-1, HSV-2), Bordetella pertussis, Chlamydia trachomatis, parvovirus B19, Treponema pallidum and varicella zoster virus (VZV). Seroprevalences for antibodies against HSV-1 were >90% in samples from Brazil and Turkey, whereas the other four countries showed lower mean age-adjusted seroprevalences (range: 62.5–87.9%). Samples from Brazilian women showed elevated seroprevalences of antibodies against HSV-2 (40.1%), C. trachomatis (46.8%) and B. pertussis (56.6%) compared to the other five countries. Seroprevalences of anti-T. gondii antibodies (0.5%) and anti-parvovirus B19 antibodies (7.5%) were low in samples from Chinese women, compared to the other five countries. Samples from German women revealed a low age-standardised seroprevalence of anti-CMV antibodies (28.8%) compared to the other five countries. These global differences in immune status of women in childbearing age advocate country-specific prophylaxis strategies to avoid infection with ToRCH pathogens.
Burnout is a state of physical, emotional and mental exhaustion. It affects talented and committed individuals working in demanding working conditions.
Although the risk of the medical community to develop the syndrome is extensively documented, this is the first study that assesses the risk of Burn Out in populations of physicians working in the pharmaceutical industry as managers,researchers or executives.
Method:
The survey was performed amongst the 175 members of the Belgian Association of Pharmaceutical Physicians. The primary objective aimed to assess the lifetime prevalence of burnout.
Maslach Burnout Inventory Scale was used to assess gravity of the components of burnout (depersonalization, professional accomplishment, emotional exhaustion).
Results:
Eighty members responded. Fifty percent suffered from burnout.
Marital status,solid social network are protecting factors. Stress antecedents aggravate the risk of relapse.
There is a relationship between occurrence of health problems and intensity of emotional exhaustion.
Demography, symptoms profile and the significant factors contributing to the risk are presented.
Conclusion:
This snapshot reveals that pharmaceutical physicians continue to be burned out at the same rate as their colleagues clinicians, not aligning on the general employee population.
Given the significant mutual investment from pharmaceutical companies and physicians in each other, prevention should be actively pursued to provide higher job satisfaction as well as better productivity.
The authors believe this findings warrant further study, possibly longitudinally, to uncover possible coping strategies and occurrence of relapse.
The regulation of poor migrants increasingly became a problem for local governments in eighteenth-century West Flanders and Flandres Maritime. Conflicts arose about which parish migrants should address for requesting poor relief. Migrants moreover physically moved over the boundaries of the different national French and Flemish legislative systems. This article will analyse how local parishes dealt with these problems in practice by focusing on a local agreement: the Concordat of Ypres of 1750. This Concordat offers an abundance of archival material and provides a unique insight into the practices of settlement and poor relief in continental Ancien Régime Europe. The aim of the article is to understand how out-parish relief functioned within the agreement. With that aim in mind, I will analyse, inter alia, the micro practices of how out-parish relief was paid (for example, removal or out-parish relief), how it reached the poor and, more importantly, how the number, expenses on and spread of out-parish poor evolved through the years. This article strengthens the claim that extensive relief practices were not unique to England and Wales. It also provides further insights into the relations between rural and urban areas (as most migration and settlement literature had either an urban or a rural focus) and sheds light on the differences of interests between local and central administrations.
The main physico-chemical properties of a new smectitic clay containing large amounts of amorphous material are reviewed and potential industrial applications of this type of clay are discussed. Due to a 34% amorphous material content (natural silica gel), the investigated clay has very high porosity and can be used as it is or in acid-impregnated form for oil bleaching or phosphate reduction in edible oil. In the field of biodiesel purification, the new clay can be used to remove, in particular, mono-, diglycerides and glycerol. The natural silica-smectite mixture is also suitable as a carrier for liquid ingredients, for example in animal feeds, and might serve as a partial or complete substitute for synthetic precipitated silicas. In the field of bioseparation processes, the clay can be used as an adsorbent for protein separation by means of cation exchange. Due to the suppressed swelling (compared with smectite alone), it can be packed in columns which can be regenerated.
Negative affect or stress is often found to increase energy intake for high palatable energy-rich foods and hence weight gain. Reduced brain serotonin (5-HT) function is known to increase stress vulnerability and the risk for eating-related disturbances. A short (S) allele polymorphism in the serotonin transporter gene (5-HTTLPR) is associated with a less efficient functioning brain serotonin system and therefore higher stress vulnerability. It has been suggested that this genotype may be directly linked to an increased risk for weight gain and/or obesity. However, a high amount of variability has been apparent in replicating such a direct gene on weight gain relationship. A most recent suggestion is that this gene by weight relationship might be moderated by an additional (cognitive) vulnerability factor involving repetitive negative thinking (rumination). Our objective was to investigate whether the S-allele of 5-HTTLPR contributes to weight gain particularly in high cognitive ruminating individuals. A total of 827 healthy young male and female college students (aged 21·3 (sd 3·0) years; BMI 16–41·7 kg/m2) were genotyped for the 5-HTTLPR polymorphism and assessed for rumination (Event Related Ruminative Index) and body weight. In line with the hypothesis, a hierarchical regression model showed that higher BMI scores were observed in specifically high ruminating S'-carriers (P=0·031, f²=0·022). These results suggest that cognitive rumination may be a critical moderator of the association between 5-HTTLPR and body mass.
Greenhouse and field experiments were conducted with a roller applicator at Lincoln, Nebraska, during 1979 and 1980. Glyphosate [N-(phosphonomethyl)glycine] concentrations of 5, 10, and 20% and carpet saturations of 50 and 75% controlled shattercane [Sorghum bicolor (L.) Moench] when applied to the top 30 cm of the plant in greenhouse research. In the field, glyphosate concentrations of 5 to 20% with a carpet saturation of 50% controlled shattercane acceptably in soybeans [Glycine max (L.) Merr.], but a concentration of 2.5% with 25% carpet saturation did not. Weed control was comparable whether speed of application was 3.2, 6.4, or 9.6 km/h. Shattercane control in grain sorghum [Sorghum bicolor (L.) Moench.] was excellent at glyphosate concentrations of 5, 10, and 20% and at carpet saturations of 50 and 75%, and sorghum injury was minimal at 25 and 50% carpet saturations. The roller applicator was compared to a ropewick applicator for shattercane control in sorghum. Excellent weed control (90% or greater) with minimal crop injury was obtained with the roller applicator at glyphosate concentrations of 10 and 20% at application speeds of 3.2 and 6.4 km/h and with the ropewick applicator with glyphosate concentrations of 35 and 50% applied at 3.2, 6.4, and 9.6 km/h.
Other research has shown that a roller applicator can selectively control weeds that protrude above the crop, conserve over 80% of the herbicide, eliminate spray drift and splash, and obviate recirculation of the spray solution. The carpet on the roller applicator must be moist enough to transfer ample herbicide to the weeds it contacts but dry enough to prevent dripping of herbicide solution from the carpet. An electronic moisture sensor and solenoid valve system was designed to permit operation of the roller applicator through various weed densities while automatically maintaining a proper level of herbicide solution in the carpet of the roller.