Surgical sterilisation is currently the method of choice for controlling free-roaming dog populations. However, there are significant logistical challenges to neutering large numbers of dogs in ...low-resource clinics. The aim of this study was to investigate the incidence of short-term surgical complications in a low-resource sterilisation clinic which did not routinely administer post-operative antibiotics. The medical records of all sterilisation surgeries performed in 2015 at the Worldwide Veterinary Service International Training Centre in Tamil Nadu, India were reviewed (group A) to assess immediate surgical complications. All animals in this group were monitored for at least 24 h post-surgery but were not released until assessed by a veterinarian as having uncomplicated wound healing. In the second part of this study from August to December 2015, 200 free-roaming dogs undergoing sterilisation surgery, were monitored for a minimum of 4-days post-surgery to further assess postoperative complications (group B).
Surgery related complications were seen in 5.4% (95%CI, 4.5-6.5%) of the 1998 group A dogs monitored for at least 24 h, and in 7.0% (3.9-11.5%) of the 200 group B dogs monitored for 4 days. Major complications were classed as those requiring an intervention and resulted in increased morbidity or mortality. Major complications were seen in 2.8% (2.1-3.6%) and 1.5% (3.1-4.3%) of group A and B, respectively. Minor complications requiring little or no intervention were recorded for 2.6% (1.9-3.4%) for group A and 5.5% (2.8-9.6%) for group B. There was no evidence for a difference in complication rates between the two groups in a multivariate regression model.
This study demonstrated that high volume, low-resource sterilisation of dogs can be performed with a low incidence of surgical complications and low mortality.
In the context of global change, symbiotic cnidarians are largely affected by seawater temperature elevation leading to symbiosis breakdown. This process, also called bleaching, is triggered by the ...dysfunction of the symbiont photosystems causing an oxidative stress and cell death to both symbiont and host cells. In our study, we wanted to elucidate the intrinsic capacity of isolated animal cells to deal with thermal stress in the absence of symbiont. In that aim, we have characterized an animal primary cell culture form regenerating tentacles of the temperate sea anemone
Anemonia viridis
. We first compared the potential of whole tissue tentacle or separated epidermal or gastrodermal monolayers as tissue sources to settle animal cell cultures. Interestingly, only isolated cells extracted from whole tentacles allowed establishing a viable and proliferative primary cell culture throughout 31 days. The analysis of the expression of tissue-specific and pluripotency markers defined cultivated cells as differentiated cells with gastrodermal origin. The characterization of the animal primary cell culture allowed us to submit the obtained gastrodermal cells to hyperthermal stress (+ 5 and + 8 °C) during 1 and 7 days. Though cell viability was not affected at both hyperthermal stress conditions, cell growth drastically decreased. In addition, only a + 8 °C hyperthermia induced a transient increase of antioxidant defences at 1 day but no ubiquitin or carbonylation protein damages. These results demonstrated an intrinsic resistance of cnidarian gastrodermal cells to hyperthermal stress and then confirmed the role of symbionts in the hyperthermia sensitivity leading to bleaching.
We demonstrate a controllable surface-coordinated linear polymerization of long-chain poly(phenylacetylenyl)s that are self-organized into a "circuit-board" pattern on a Cu(100) surface. Scanning ...tunneling microscopy/spectroscopy (STM/S) corroborated by ab initio calculations, reveals the atomistic details of the molecular structure, and provides a clear signature of electronic and vibrational properties of the poly(phenylacetylene)s chains. Notably, the polymerization reaction is confined epitaxially to the copper lattice, despite a large strain along the polymerized chain that subsequently renders it metallic. Polymerization and depolymerization reactions can be controlled locally at the nanoscale by using a charged metal tip. This control demonstrates the possibility of precisely accessing and controlling conjugated chain-growth polymerization at low temperature. This finding may lead to the bottom-up design and realization of sophisticated architectures for molecular nano-devices.
Recent experimental reports indicate that Joule heating can atomically sharpen the edges of chemical vapor deposition grown graphitic nanoribbons. The absence or presence of loops between adjacent ...layers in the annealed materials is the topic of a growing debate that this Letter aims to put to rest. We offer a rationale explaining why loops do form if Joule heating is used alone, and why adjacent nanoribbon layers do not coalesce when Joule heating is applied after high-energy electrons first irradiate the sample. Our work, based on large-scale quantum molecular dynamics and electronic-transport calculations, shows that vacancies on adjacent graphene sheets, created by electron irradiation, inhibit the formation of edge loops.
More so than the traditional fixed radiometers, the scanning radiometer requires a careful design to ensure high quality measurements. Here the impact of the radiometer characteristics (e.g., antenna ...beam width and receiver bandwidth) and atmospheric propagation (e.g. curvature of the Earth and vertical gradient of refractive index) on scanning radiometer measurements are presented. A forward radiative transfer model that includes all these effects to represent the instrument measurements is used to estimate the biases. These biases are estimated using differences between the measurement with and without these characteristics for three commonly used frequency bands: K, V and W-band. The receiver channel bandwidth errors are less important in K-band and W-band. Thus, the use of a wider bandwidth to improve detection at low signal-to-noise conditions is acceptable at these frequencies. The biases caused by omitting the antenna beam width in measurement simulations are larger than those caused by omitting the receiver bandwidth, except for V-band where the bandwidth may be more important in the vicinity of absorption peaks. Using simple regression algorithms, the effects of the bandwidth and beam width biases in liquid water path, integrated water vapour, and temperature are also examined. The largest errors in liquid water path and integrated water vapour are associated with the beam width errors.
There is no systematic procedure described in the literature to establish a robust and accurate reference method for determining the moisture content in any solid food product. In this paper, we are ...proposing a new approach based on simultaneous thermogravimetry and differential thermal analysis (TG–DTA), with data for several amorphous food powders that result from spray-drying, freeze-drying or extrusion. In the first step, by heating a representative sample of about 20
mg at 2
°C/min we would detect the temperature and the mass loss at the inflection point that characterises, if there is an inflection, the end of the drying and the onset of chemical reactions. In cases of not too much sensitive products, the mass loss at the inflection may be considered as a good estimation of the moisture content. At 2
°C/min heating rate, the inflection temperature
T
i is an indicator that allows estimating the optimal isothermal drying temperature
T
d about 15–30
°C below
T
i, depending on the product sensitivity to heat treatments and the kinetics of water molecule diffusion through the amorphous matrix. Then, a series of three isothermal drying are performed at about
T
d−12
°C,
T
d and
T
d+8
°C, and a simple multilinear model allows calculating the best oven temperature to achieve the optimal moisture content determination in 2
h. This procedure is described and results are shown for several dehydrated food products: milk, coffee, cereal and pet food. This fast procedure may be applied either for establishing optimal oven conditions for most amorphous new products or for revising conditions that have been established in the past but are not robust enough for several ones.
A fascinating structural transformation occurring inside single-walled carbon nanotubes (SWNTs) is the fullerene coalescence, which is responsible for forming stable zeppelinlike carbon molecules. We ...report in situ transmission electron microscope (TEM) observations revealing sequences of fullerene coalescence induced by electron irradiation on pristine nanotube peapods, together with extensive theoretical investigations of the microscopic mechanism underlying this process. TEM images indicate that the merging of fullerenes results in stable but corrugated tubules (5 to 7 Å in diameter) confined within SWNTs. These observations have been confirmed using a combination of theoretical approaches based on molecular dynamics, empirical potentials, tight-binding methods, Monte Carlo techniques, and first principles calculations. We have fully elucidated the coalescence mechanism of fullerenes inside SWNTs under electron irradiation and thermal annealing. The process occurs via the polymerization of C60 molecules followed by surface reconstruction, which can be triggered either by the formation of vacancies (created under electron irradiation) or by surface-energy minimization activated by thermal annealing. These novel tubular forms of carbon contain hexagons, pentagons, heptagons, and octagons. The stability, electronic properties, and electron conductance of the novel tubules are strongly affected by the final geometry of the coalesced fullerene complex. The possibility of forming highly conducting and semiconducting tubular structures suggests new avenues in designing carbon nanowires with specific electronic characteristics.
Field emission properties of B-doped carbon nanotubes are investigated from both theoretical and experimental standpoints. Using tight-binding and ab initio calculations, it is observed that ...B-saturating tip edges of carbon nanotubes induce the presence of large peaks within the local density of states (LDOS) located in an energy region close to the Fermi level (Ef). These localized states suggest a field emission enhancement for the B-doped tubes. In addition, ab initio theoretical results indicate that the work function for B-doped tubes is 1.7 eV lower when compared to pure carbon-terminated nanotubes. Experimentally, it is found that B-doped tubes, which are produced by arc discharge techniques and contain B mainly at the tips, exhibit stable electron field emission at lower turn-on voltages (1.4 V/μm) when compared to pure single- and multiwalled carbon nanotubes (2.8 and 3.0 V/μm, respectively) measured under the same conditions. We strongly believe our results will bring new insights in the fabrication of stable field emission sources.
Cytochrome P450 chemical inhibitors are widely used to define the role of individual cytochrome P450 isozyme(s) in a metabolism process. In this study, cytochrome P450 isoform-dependent reactions ...were investigated on our human liver microsomes bank (n = 34) and characterized for both KM and VMAX values (n > or = 3). These metabolic reactions were: 7-ethoxyresorufin O-deethylation (CYP1A1), phenacetin O-deethylation (CYP1A2), coumarin 7-hydroxylation (CYP2A6), tolbutamide 4-methylhydroxylation (CYP2C9), dextromethorphan O-demethylation (CYP2D6), aniline 4-hydroxylation (CYP2E1) and nifedipine dehydrogenation (CYP3A4). Literature data-based specific inhibitors were selected and characterized for both their inhibitory constant (Ki) and the inhibition-type toward their specific substrate. Results were as follows: alpha-naphthoflavone (CYP1A1; mixed-type interaction with a Ki = 0.01 microM), furafylline (CYP1A2; competitive-type interaction with a Ki = 3 microM when microsomes were incubated with both furafylline and phenacetin; noncompetitive-type interaction with a Ki = 0.6 microM when microsomes were preincubated with furafylline and NADPH), pilocarpine (CYP2A6; competitive-type interaction with a Ki = 4 microM), sulfaphenazole (CYP2C9; competitive-type interaction with a Ki = 0.3 microM), quinidine (CYP2D6; competitive-type interaction with a Ki = 0.4 microM, diallyldisulfide (CYP2E1; noncompetitive-type interaction with a Ki = 150 microM on an aniline concentration range of 10-60 microM; competitive-type interaction with a Ki = 100 microM on an aniline concentration range of 80-2000 microM) and ketoconazole (CYP3A4; mixed-type interaction with a Ki = 0.015 microM). Once the inhibitors' potency was determined, the selective effects of these inhibitors were evaluated after incubation of human hepatic microsomes with isoform-selective substrates in the presence of the different chemical inhibitors. Up to 10 times the Ki value toward the isoform-selective probe, pilocarpine, sulfaphenazole, quinidine and ketoconazole exhibited potent inhibitory and specific effects. alpha-Naphthoflavone and furafylline both inhibited phenacetin and 7-ethoxyresorufin O-deethylation processes, a consequence of the absence of CYP1A1 in noninduced human liver. Diallyldisulfide exhibited broad and nonspecific inhibitory effects. When used in their "window of selectivity," ie., up to 10-fold the Ki value, most chemical inhibitors powerfully and specifically inhibited cytochrome P450 isoform-specific reactions when analyzed at their KM values.
•Spin valve effect in rhombic graphene quantum dot controlled by B/N doping.•The B/N doping gives rise the semiconductor-to-metal transition in rGQD leading to high spin-filter efficiency.•Spin ...injection in AGNR electrodes from rhombic graphene quantum dot.
Spin-polarized transport through a rhombic graphene quantum dot (rGQD) attached to armchair graphene nanoribbon (AGNR) electrodes is investigated by means of the Green’s function technique combined with single-band tight-binding (TB) approach including a Hubbard-like term. The Hubbard repulsion was included within the mean-field approximation. Compared to anti-ferromagnetic (AFM), we show that the ferromagnetic (FM) ordering of the rGQD corresponds to a smaller bandgap, thus resulting in an efficient spin injector. As a consequence, the electron transport spectrum reveals a spin valve effect, which is controlled by doping with B/N atoms creating a p-n-type junction. The calculations point out that such systems can be used as spin-filter devices with efficiency close to a 100%.
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