Context.
We present results from the first recorded stellar occultation by the large trans-Neptunian object (174567) Varda that was observed on September 10, 2018. Varda belongs to the ...high-inclination dynamically excited population, and has a satellite, Ilmarë, which is half the size of Varda.
Aims.
We determine the size and albedo of Varda and constrain its 3D shape and density.
Methods.
Thirteen different sites in the USA monitored the event, five of which detected an occultation by the main body. A best-fitting ellipse to the occultation chords provides the instantaneous limb of the body, from which the geometric albedo is computed. The size and shape of Varda are evaluated, and its bulk density is constrained using Varda’s mass as is known from previous works.
Results.
The best-fitting elliptical limb has semi-major (equatorial) axis of (383 ± 3) km and an apparent oblateness of 0.066 ± 0.047, corresponding to an apparent area-equivalent radius
R
′
equiv
= (370±7) km and geometric albedo
p
v
= 0.099 ± 0.002 assuming a visual absolute magnitude
H
V
= 3.81 ± 0.01. Using three possible rotational periods for the body (4.76, 5.91, and 7.87 h), we derive corresponding MacLaurin solutions. Furthermore, given the low-amplitude (0.06 ± 0.01) mag of the single-peaked rotational light-curve for the aforementioned periods, we consider the double periods. For the 5.91 h period (the most probable) and its double (11.82 h), we find bulk densities and true oblateness of
ρ
= (1.78 ± 0.06) g cm
−3
,
ɛ
= 0.235 ± 0.050, and
ρ
= (1.23 ± 0.04) g cm
−3
,
ɛ
= 0.080 ± 0.049. However, it must be noted that the other solutions cannot be excluded just yet.
Caprella scaura
(Templeton in Trans Entomol Soc Lond 1:185–198,
1836
) is a native species to the western Indian Ocean. It was first described from Mauritius and later reported from several regions ...of the world. During the last decade, the species spread out of the Adriatic Sea, and in 2005,
C. scaura
was reported in Gerona, on the north-eastern coast of Spain. The present study shows the recent rapid expansion of the species to the East Atlantic. During a sampling survey of harbours along the Strait of Gibraltar (Dec 2009–June 2010), we found high densities of
C. scaura
associated with the bryozoans
Zoobotryon verticillatum
Della Chiaje, 1822, in Chipiona and
Bugula neritina
(L.) in Cádiz, Atlantic coast of southern Spain; on the other hand, during May 2009, an important population of
C. scaura
was also found in the Canary Islands (Tenerife) associated with aquaculture resources. A total of 1,034 individuals of
C. scaura
were studied, and we confirm that the populations are effectively established, with high densities and reproducing females during the whole year. The population from Cádiz was characterised by smaller specimens but a higher number of eggs per female. These differences could be related to environmental conditions, mainly sea water temperature and to other factors such as competition with other species, or availability of food or substrate. Significant correlation was found between female size and number of eggs in the three populations, but egg size did not vary with female body length. The morphometric relation length/width of the second gnathopod was also calculated and compared between sexes: larger males presented longer gnathopods at the three sites. The most probable introduction vector of this species is shipping; in fact, the Strait of Gibraltar is characterised by an intense shipping traffic. Also, we have observed that the native
Caprella equilibra
Say, 1818, is being displaced by
C. scaura
in the harbour of Cádiz, where this species reach densities of 35,945 ind/1,000 g of
B. neritina
. Further experimental studies are necessary to explore the potential danger of this species, which might spread into natural habitats too.
Visceral leishmaniasis (VL) is a rare disease in solid-organ transplant (SOT) recipients. Therefore, little is known about the risk factors and disease behavior in the transplant setting. This ...multicenter, matched case–control study (1:2 ratio) was designed to determine the risk factors, clinical features and outcomes of VL among this population. Control and case subjects were matched by center, transplant type and timing. Thirty-six VL cases were identified among 25 139 SOT recipients (0.1%). VL occurred 5.7-fold more frequently in Brazil than in Spain, presenting a median time of 11 months after transplantation. High-dose prednisone in the preceding 6 months was associated with VL. Patients were diagnosed over 1 month after symptom onset in 25% of cases. Thirty-one patients (86%) were febrile upon diagnosis, 81% exhibited visceromegaly and 47% showed pancytopenia. Concomitant infection was common. Parasites were identified in 89% of patients; the remaining patients were diagnosed by serology. The majority of the patients received amphotericin B. Relapses occurred in 25.7% of cases, and the crude mortality rate was 2.8%. VL after SOT is related to the VL prevalence in the general population. Delayed diagnosis frequently occurs. Liposomal amphotericin is the most commonly used therapy; mortality is low, although relapses are common.
As part of the 2002 Shelf-Basin Interactions (SBI) process study, measurements of the seasonal variation in the export flux of particulate organic carbon (POC) are reported for the upper waters of ...the Chukchi Sea. POC fluxes were quantified by determination of
234Th/
238U disequilibrium and POC/
234Th ratios in large
(
>
53
μ
m
)
aggregates collected using in situ pumps. Samples were collected at 35 stations on two cruises, one in predominantly ice-coved conditions during the spring (May 6–June 15) and the other in predominantly open water during the summer (July 17–August 26). Enhanced particle export was observed in the shelf and slope waters, particularly within Barrow Canyon, and there was a marked increase in particle export at all stations during the summer (July–August) relative to the spring (May–June).
234Th-derived POC fluxes exhibit significant seasonal and spatial variability, averaging
2.9
±
5.3
mmol
C
m
-
2
d
-
1
(
range
=
0.031
–
22
mmol
C
m
-
2
d
-
1
)
in the spring and increasing
∼
4
-fold in the summer to an average value of
10.5
±
9.3
mmol
C
m
-
2
d
-
1
(
range
=
0.79
–
39
mmol
C
m
-
2
d
-
1
)
. The fraction of primary production exported from the upper waters increases from
∼
15
%
in the spring to
∼
32
%
in the summer. By comparison, DOC accumulation associated with net community production represented
∼
6
%
of primary production
(
∼
2
mmol
C
m
-
2
d
-
1
)
. The majority of shelf and slope stations indicate a close agreement between POC export and benthic C respiration in the spring, whereas there is an imbalance between POC export and benthic respiration in the summer. The implication is that up to
∼
20
%
of summer production
(
∼
6
±
7
mmol
C
m
-
2
d
-
1
)
may be seasonally exported off-shelf in this productive shelf/slope region of the Arctic Ocean.
Burkholderia anthina
XXVI is a rhizosphere bacterium isolated from a mango orchard in Mexico. This strain has a significant biological control activity against the causal agent of mango anthracnose,
...Colletotrichum gloeosporioides
, likely through the production of siderophores and other secondary metabolites. Here, we present a draft genome sequence of
B. anthina
XXVI (approximately 7.7 Mb; and G + C content of 67.0%), with the aim of gaining insight into the genomic basis of antifungal modes of action, ecological success as a biological control agent, and full biosynthetic potential.
Antioxidant, anticarcinogenic, and antimicrobial properties have been reported for ferulic acid (FA), therefore, its application interests both food and agriculture research. FA was immobilized in ...different chitosan (CS) matrices, physicochemicaly characterized and the effect on Aspergillus parasiticus ecological parameters evaluated. Nanoparticles (Nparticles), microparticles (Mparticles) and microcapsules (Mcapsules) of 35-40 nm, 30-40 μm, and 20 μm, respectively were obtained; FA incorporation in matrices affected their morphology, physicochemical properties, and their fungistatic effect. The effect of the particles was dependent on the matrix exposed. Nparticles and Mparticles showed high FA immobilization efficiency as well as a good fungistatic effect against A. parasiticus: Radial growth at 168 h was 28.46 ± 1.01 and 28.84 ± 1.36 and the inhibition of spore germination at 30 h was 57.44 ± 0.22 and 55.74 ± 2.19, for Nparticles and Mparticles, respectively compared with control cultures. Abnormalities in mycelium, hyphae, and spores morphology were observed, as well as low sporulation due particle interaction with the fungus.
Treatment of craniomaxillofacial (CMF) trauma in dogs often requires a multidisciplinary approach and a thorough understanding of the CMF anatomical structures involved. This retrospective study ...aimed to utilize computed tomography (CT) studies of immature dogs evaluated for CMF trauma and to describe common fracture locations, treatment modalities, and complications, as well as the fracture healing outcomes. The medical records and CT studies of 94 dogs under 1 year of age over a 13-year period were evaluated. The skeletal location of CMF fractures, as well as the severity of displacement and fragmentation of each fracture, was recorded. Case demographic data and trauma etiology were also recorded. Animal bites accounted for the majority of trauma (71.0%). The most likely bone or region to be fractured was the maxillary bones, followed by the molar region of the mandibles. Up to 37 bones or specific regions were fractured in any given patient, with an average of 8.8 ± 3.1 fractured bones or regions per dog. Rostral mandibular trauma was associated with intra-articular fractures of the temporomandibular joint (
p
= 0.016). Patients sustained concomitant injuries in 32% of the cases. Muzzle therapy was the main treatment performed for most dogs (53.2%), followed by soft tissue closure (47.9%) and selective dental extractions (27.6%). Healing complications were recorded in 71.6% of the dogs, with malocclusion being the most reported complication (55.2%), and associated with dentate mandibular jaw fractures (
p
= 0.05). The average number of complications per dog was 2.4. No statistically significant association was found between treatment modality and healing outcome. There was a positive correlation between the severity of fracture fragmentation and displacement and a negative healing outcome (all rho >0.7). Further treatment was required in 55.6% of the dogs. Additional dental extractions were performed in 77.7% of patients. Healing complications were common in the immature CMF trauma case. Thus, the need for a comprehensive assessment of the entire CMF region during the initial visit, as well as follow-up, preferably using CT or cone beam CT, is underscored.
Spectroscopic and colorimetric analysis of a representative set of Dugès watercolor paintings was performed. These paintings were the result of scientific studies carried out by the zoologist Alfredo ...Dugès, who recorded the fauna of the Mexican Republic between 1853 and 1910. Micro-Raman spectroscopy, with an excitation wavelength of 830
nm, and colorimetric techniques were employed in order to understand if different colors with the same hue were reproduced using the same pigments. The color coordinates of the measured areas were obtained in the CIE
L*
a*
b* color space. Raman analysis showed that, in some cases, to reproduce colors with the same hue the pigment employed was not the same. Pigments identified in the watercolors were vermilion, carbon-based black, lead white, gamboge and chrome yellow, Prussian and ultramarine blue. Some of these pigments have been used since ancient times, others as Prussian blue, chrome yellow and synthetic ultramarine blue arrived to the market at the beginning of the 18th and 19th centuries, respectively. Furthermore, regarding the white color, instead of left the paper unpainted, lead white was detected in the eye of a bird. The green color was obtained by mixing Prussian blue with chrome yellow. The results of this work show the suitability of using Raman spectroscopy for watercolor pigment analysis and colorimetric techniques to measure the color of small areas (246
μm
×
246
μm) that was the case for the lead white pigment.
Background
Recruitment into surgical RCTs can be threatened if new interventions available outside the trial compete with those being evaluated. Adapting the trial to include the new intervention may ...overcome this issue, yet this is not often done in surgery. This paper describes the challenges, rationale and methods for adapting an RCT to include a new intervention.
Methods
The By‐Band study was designed in the UK in 2009–2010 to compare the effectiveness of laparoscopic adjustable gastric band and Roux‐en‐Y gastric bypass for severe obesity. It contained a pilot phase to establish whether recruitment was possible, and the grant proposal specified that an adaptation to include sleeve gastrectomy would be considered if practice changed and recruitment was successful. Information on changing obesity surgery practice, updated evidence and expert opinion about trial design were used to inform the adaptation.
Results
The pilot phase recruited over 13 months in 2013–2014 and randomized 80 patients (79 anticipated). During this time, major changes in obesity practice in the UK were observed, with gastric band reducing from 32·6 to 15·8 per cent and sleeve gastrectomy increasing from 9·0 to 28·1 per cent. The evidence base had not changed markedly. The British Obesity and Metabolic Surgery Society and study oversight committees supported an adaptation to include sleeve gastrectomy, and a proposal to do so was approved by the funder.
Conclusion
Adaptation of a two‐group surgical RCT can allow evaluation of a third procedure and maintain relevance of the RCT to practice. It also optimizes the use of existing trial infrastructure to answer an additional important research question. Registration number: ISRCTN00786323 (http://www.isrctn.com/).
Something to consider
This article presents an Evolution Strategy (ES)--based algorithm, designed to self-adapt its mutation operators, guiding the search into the solution space using a Self-Adaptive Reduced Variable ...Neighborhood Search procedure. In view of the specific local search operators for each individual, the proposed population-based approach also fits into the context of the Memetic Algorithms. The proposed variant uses the Greedy Randomized Adaptive Search Procedure with different greedy parameters for generating its initial population, providing an interesting exploration–exploitation balance. To validate the proposal, this framework is applied to solve three different
-Hard combinatorial optimization problems: an Open-Pit-Mining Operational Planning Problem with dynamic allocation of trucks, an Unrelated Parallel Machine Scheduling Problem with Setup Times, and the calibration of a hybrid fuzzy model for Short-Term Load Forecasting. Computational results point out the convergence of the proposed model and highlight its ability in combining the application of move operations from distinct neighborhood structures along the optimization. The results gathered and reported in this article represent a collective evidence of the performance of the method in challenging combinatorial optimization problems from different application domains. The proposed evolution strategy demonstrates an ability of adapting the strength of the mutation disturbance during the generations of its evolution process. The effectiveness of the proposal motivates the application of this novel evolutionary framework for solving other combinatorial optimization problems.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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