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The repetitive use of ALS-inhibitors for Cyperus difformis L. control has selected for herbicide-resistant (R) populations, which threaten the sustainability of rice production and demand alternative control measures to be developed. A better understanding of seedling recruitment patterns at the field level is required to optimize the timing and efficacy of control measures. Therefore, a population-based threshold model was developed for optimizing germination prediction in multiple ALS-R and –S (susceptible) C. difformis biotypes and applied to field-level emergence predictions. Estimated base temperatures (Tb) ranged from 16.5 to 17.6 °c with no clear pattern between biotypes; such values are higher than Tb of other important rice weeds, as well as for rice. Germination rates increased linearly from 16 to 33.7 °c. ALS-R seeds germinate faster due to smaller median thermal times to germination (θT(50)) while also displaying lower germination synchronicity across water potentials. Interestingly, ALS-R biotypes were capable of germinating under lower moisture availability, as indicated by their lower (more negative) base water potential values (Ψb(50)) for seed germination; Ψb(50) values ranged from -0.24 to -1.13 MPa. In-field soil germination measurements found thermal-times to emergence varied across three water regimes (daily water, flooded, or saturated). Seedling emergence under the daily water treatment was fastest; however, total seedling density lower than for the other water regimes. In order to optimize springtime C. difformis seedling emergence, soil moisture should be kept around field capacity, as germination is hindered at lower moisture contents. By predicting when most of the seed population germinates, the thermal-time model can address issues regarding the optimal timing for herbicide applications, thereby allowing for improved C. difformis management in rice fields.
The first positive genome-wide association study on gestational length and preterm delivery showed associations with a gene involved in the selenium metabolism. In this study we examine the associations between maternal intake of selenium and selenium status with gestational length and preterm delivery in 72,025 women with singleton live births from the population based, prospective Norwegian Mother, Father and Child Cohort Study (MoBa). A self-reported, semi-quantitative food-frequency questionnaire answered in pregnancy week 22 was used to estimate selenium intake during the first half of pregnancy. Associations were analysed with adjusted linear and cox regressions. Selenium status was assessed in whole blood collected in gestational week 17 (n=2,637). Median dietary selenium intake was 53 (IQR: 44-62) µg/day, supplements provided additionally 50 (30-75) µg/day for supplement-users (n=23,409). Maternal dietary selenium intake was significantly associated with prolonged gestational length (β per SD=0.25, 95% CI=0.07-0.43) and decreased risk for preterm delivery (n=3,618, HR per SD=0.92, 95% CI=0.87-0.98). Neither selenium intake from supplements nor maternal blood selenium status was associated with gestational length or preterm delivery. Hence, this study showed that maternal dietary selenium intake, but not intake of selenium containing supplements, during the first half of pregnancy was significantly associated with decreased risk for preterm delivery. Further investigations, preferably in the form of a large RCT, are needed to elucidate the impact of selenium on pregnancy duration.
be a configuration of
. Each pair of points has a Euclidean distance in the configuration. Given some graph
vertices, we measure the point-pair distances corresponding to the edges of
. In this paper, we study the question of when a generic
dimensions will be uniquely determined (up to an unknowable Euclidean transformation) from a given set of point-pair distances together with knowledge of
. In this setting the distances are given simply as a set of real numbers; they are not labeled with the combinatorial data that describes which point pair gave rise to which distance, nor is data about
given. We show, perhaps surprisingly, that in terms of generic uniqueness, labels have no effect. A generic configuration is determined by an unlabeled set of point-pair distances (together with
) if and only if it is determined by the labeled distances.
Describe the epidemiological and molecular characteristics of an outbreak of Klebsiella pneumoniae carbapenemase (KPC)–producing organisms and the novel use of a cohorting unit for its control.
A 566-room academic teaching facility in Milwaukee, Wisconsin.
Solid-organ transplant recipients.
Infection control bundles were used throughout the time of observation. All KPC cases were intermittently housed in a cohorting unit with dedicated nurses and nursing aids. The rooms used in the cohorting unit had anterooms where clean supplies and linens were placed. Spread of KPC-producing organisms was determined using rectal surveillance cultures on admission and weekly thereafter among all consecutive patients admitted to the involved units. KPC-positive strains underwent pulsed-field gel electrophoresis and whole-genome sequencing.
A total of 8 KPC cases (5 identified by surveillance) were identified from April 2016 to April 2017. After the index patient, 3 patients acquired KPC-producing organisms despite implementation of an infection control bundle. This prompted the use of a cohorting unit, which immediately halted transmission, and the single remaining KPC case was transferred out of the cohorting unit. However, additional KPC cases were identified within 2 months. Once the cohorting unit was reopened, no additional KPC cases occurred. The KPC-positive species identified during this outbreak included Klebsiella pneumoniae, Enterobacter cloacae complex, and Escherichia coli. blaKPC was identified on at least 2 plasmid backbones.
A complex KPC outbreak involving both clonal and plasmid-mediated dissemination was controlled using weekly surveillances and a cohorting unit.
Although shyness is a ubiquitous phenomenon with early developmental origins, little research has examined the influence of prenatal exposures on the developmental trajectory of shyness. Here, we examined trajectories of shyness from childhood to adulthood in three groups (N = 254), with varying degrees of prenatal adversity as indicated by the number of stressful exposures: extremely low birth weight (ELBW; <1000 g) survivors prenatally exposed to exogenous corticosteroids (ELBW+S, n = 56); ELBW survivors not prenatally exposed to exogenous corticosteroids (ELBW+NS, n = 56); and normal birth weight (NBW, n = 142) controls. Multilevel modeling revealed that the ELBW+S individuals exhibited the highest levels of childhood shyness, which remained stable into adulthood. The ELBW+NS and NBW controls had comparably low levels of childhood shyness; however, the ELBW+NS individuals experienced patterns of increasing shyness, while NBW controls displayed decreases in shyness into adulthood. We speculate that individuals exposed to multiple prenatal stressors (i.e., ELBW+S) may be developmentally programmed to be more sensitive to detecting social threat, with one manifestation being early developing, stable shyness, while increasing shyness among ELBW+NS individuals may reflect a later developing shyness influenced by postnatal context. We discuss the implications of these findings for understanding the developmental origins and developmental course of human shyness from childhood through adulthood.
We study a restricted form of list colouring, for which every pair of lists that correspond to adjacent vertices may not share more than one colour. The optimal list size such that a proper list colouring is always possible given this restriction, we call separation choosability. We show for bipartite graphs that separation choosability increases with (the logarithm of) the minimum degree. This strengthens results of Molloy and Thron and, partially, of Alon. One attempt to drop the bipartiteness assumption precipitates a natural class of Ramsey-type questions, of independent interest. For example, does every triangle-free graph of minimum degree d contain a bipartite induced subgraph of minimum degree Ω(log d) as d→∞?
Intestate succession statutes should reflect the distributive preferences of intestate decedents. To date, these distributive preferences could only be inferred from distributive patterns found in wills. This telephone survey of 750 persons living in Alabama, California, Massachusetts, Ohio, and Texas supplements prior will studies and provides new insights concerning public attitudes about property distribution at death. The distributive preferences of the respondents revealed few significant differences that could be attributed to age, education, income, wealth, or occupational status. Two other important findings of this study suggest that a modern intestacy statute should provide that (1) the surviving spouse inherit the entire estate in preference to the decedent's issue or family of orientation and (2) issue who are in the same generation share equally in the estate.
Mothers’ return to work and childcare providers’ support for feeding expressed human milk are associated with breast-feeding duration rates in the USA, where most infants are regularly under non-parental care. The objective of the present study was to explore Florida-based childcare centre administrators’ awareness and perceptions of the Florida Breastfeeding Friendly Childcare Initiative.
Semi-structured interviews were based on the Consolidated Framework for Implementation Research and analysed using applied thematic analysis.
Childcare centre administrators in Tampa Bay, FL, USA, interviewed in 2015.
Twenty-eight childcare centre administrators: female (100 %) and Non-Hispanic White (61 %) with mean age of 50 years and 13 years of experience.
Most administrators perceived potential implementation of the Florida Breastfeeding Friendly Childcare Initiative as simple and beneficial. Tension for change and a related construct (perceived consumer need for the initiative) were low, seemingly due to formula-feeding being normative. Perceived financial costs and relative priority varied. Some centres had facilitating structural characteristics, but none had formal breast-feeding policies.
A cultural shift, facilitated by state and national breast-feeding-friendly childcare policies and regulations, may be important for increasing tension for change and thereby increasing access to breast-feeding-friendly childcare. Similar to efforts surrounding the rapid growth of the Baby Friendly Hospital Initiative, national comprehensive evidence-based policies, regulations, metrics and technical assistance are needed to strengthen state-level breast-feeding-friendly childcare initiatives.
The origins of agriculture in South-west Asia is a topic of continued archaeological debate. Of particular interest is how agricultural populations and practices spread inter-regionally. Was the Arabian Neolithic, for example, spread through the movement of pastoral groups, or did ideas perhaps develop independently? Here, the authors report on recent excavations at Alshabah, one of the first Neolithic sites discovered in Northern Arabia. The site’s material culture, environmental context and chronology provide evidence suggesting that well-adapted, seasonally mobile, pastoralist groups played a key role in the Neolithisation of the Arabian Peninsula.
Designing effective control for complex three-dimensional flow fields proves to be non-trivial. Often, intuitive control strategies lead to suboptimal control. To navigate the control space, we use a linear parabolized stability analysis to guide the design of a control scheme for a trailing vortex flow field aft of a NACA0012 half-wing at an angle of attack
and a chord-based Reynolds number
. The stability results show that the unstable mode with the smallest growth rate (fifth wake mode) provides a pathway to excite a vortex instability, whereas the principal unstable mode does not. Inspired by this finding, we perform direct numerical simulations that excite each mode with body forces matching the shape function from the stability analysis. Relative to the uncontrolled case, the controlled flows show increased attenuation of circulation and peak streamwise vorticity, with the fifth-mode-based control set-up outperforming the principal-mode-based set-up. From these results, we conclude that a rudimentary linear stability analysis can provide key insights into the underlying physics and help engineers design effective physics-based flow control strategies.
Paragonimiasis, human lung fluke disease, is a foodborne anthropozoonosis caused by the trematodes assigned to Paragonimus and is regarded by the World Health Organization as a Neglected Tropical Disease (NTD). The life cycle of this medically important parasite centres on a complex freshwater biological community that includes two intermediate hosts: a mollusc and a decapod, usually a brachyuran. Although there is a perception that the biology, symptoms, diagnosis and treatment of Paragonimus is well understood, in reality, this is not the case, especially in Africa. Much remains unknown concerning the life-cycle of the parasite, its transmission, the current epidemiology of the disease, diagnosis and the effectiveness of treatment. Furthermore, cases of paragonimiasis may be misdiagnosed as resistant tuberculosis (TB) because of the similar pulmonary symptoms and no remission after anti TB therapy. The endemic foci of human paragonimiasis in Africa have been reported mainly in the forest zones of Upper Guinea (Liberia, Guinea and Ivory Coast) and Lower Guinea (Nigeria, Cameroon, Equatorial Guinea and Gabon). Despite the perceived medical importance of paragonimiasis, relatively little attention has been paid to this NTD since its discovery in Africa in the 1960s. This review focuses on the current understanding of the life cycle and transmission of Paragonimus in Africa, discusses its diagnosis and public health importance and highlights many outstanding gaps in the knowledge that still exist for this NTD.
Oldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.
Juridical protection of the rights of nature is steadily emerging in several legal systems and in public discourse. Building on a recent publication in Transnational Environmental Law in which we interrogated Ecuador’s constitutional experiment with the rights of nature, we critically reflect in this contribution on Bolivia’s legal regime providing for the rights of Mother Earth. We do so, first, by sketching the juridical-political context within which these statutes were drafted and adopted, and then by analyzing the relevant constitutional provisions that provide the basis for the laws of Mother Earth. The third part forms the bulk of the discussion and details the background and the most relevant provisions of Bolivian statutes with a view to enabling a deeper critique in Part 4, in which we critically evaluate both the symbolic and the theoretical significance of the statutes as well as concerns related to their practical implementation. Insofar as the rights of nature paradigm has now become a truly global debate and a consideration in transnational comparative legal borrowing practices, our analysis aims to reveal the Bolivian experience, which could be instructive for civil society groups, academics, politicians and legislatures in a transnational setting.
Late prehistoric archaeological research in Myanmar is in a phase of rapid expansion. Recent work by the Mission Archéologique Française au Myanmar aims to establish a reliable Neolithic to Iron Age culture-historical sequence, which can then be compared to surrounding regions of Southeast Asia. Excavations at Nyaung'gan and Oakaie in central Myanmar have provided 52 new AMS dates, which allow the creation of Myanmar's first reliable prehistoric radiometric chronology. They have also identified the Neolithic to Bronze Age transition in central Myanmar, which is of critical importance in understanding long-range interactions at the national, regional and inter-regional level. This research provides the first significant step towards placing late prehistoric Myanmar in its global context.