In this work, we obtain good upper bounds for the diameter of any graph in terms of its minimum degree and its order, improving a classical theorem due to Erdos, Pach, Pollack and Tuza. We use these bounds in order to...
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In this work, we obtain good upper bounds for the diameter of any graph in terms of its minimum degree and its order, improving a classical theorem due to Erdos, Pach, Pollack and Tuza. We use these bounds in order to study hyperbolic graphs (in the Gromov sense). To compute the hyperbolicity constant is an almost intractable problem, thus it is natural to try to bound it in terms of some parameters of the graph. Let H(n, δ0) be the set of graphs G with n vertices and minimum degree 50, and J(n, Δ) be the set of graphs G with n vertices and maximum degree A. We study the four following extremal problems on graphs: a(n,δ0) = min{δ(G) | G ∈H(n, δ0)}, b(n, δ0) =- max{δ(G)| e ∈H(n, δ0)}, α(n, Δ) = min{δ(G) [ G ∈ J(n, Δ)} and β(n,Δ) = max{δ(G) ] G∈Π(n,Δ)}. In particular, we obtain bounds for b(n, δ0) and we compute the precise value of a(n, δ0), α(n, Δ) and w(n, Δ) for all values of n, r0 and A, respectively.
作者:
Terrence jose JeromeOrthopedics
Hand and Reconstructive MicrosurgeryOlympia Hospital&Research CentreTiruchirappalliIndia
Background Many studies have discussed acute compartment syndrome in children associated with or without fractures and have given their visible *** is known about the nerve involvement and the factors associated with ...
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Background Many studies have discussed acute compartment syndrome in children associated with or without fractures and have given their visible *** is known about the nerve involvement and the factors associated with recovery patterns in these *** intend to propose that ischemic nerve and muscles tend to regenerate after surgical decompression but in a different pattern and the given *** Twenty-four children with acute compartment syndrome in the upper limb were analyzed between 2009 and *** included demographic features of these patients,the time interval between the injury and surgery,and the attempt to correlate with motor and sensory *** The average follow-up was 67.3 months(range 59-80).Of the 24,14 patients(58%)had immediate recovery of motor and sensory *** remaining 10 patients had variable recovery patterns with a mean time for the radial nerve,median nerve and ulnar nerve motor recovery of 6.0,7.5 and 8.5 months,respectively,and sensory recovery at 12,12 and 13 months,*** overall study had a mean sensory recovery as per the Medical Research Council(MRC)of S3 in 3(12%)and S4 in 21(88%).The mean 2-point discrimination(2PD)was 6.9 mm(range 5-10).Twenty-one patients(88%)had a full range of movements at their final follow-up with a mean Visual Analog Scale score of 0.6;a quick Disabilities of the Arm,Shoulder and Hand score of 5.9(range 2.3-25.0)and a Mayo wrist score of *** There was a definite motor and sensory recovery in patients who underwent surgical decompression in acute compartment syndrome of the upper limb irrespective of age,gender,delay in presentation and various *** motor and nerve fibers can regenerate after ischemic sequela of compartment syndrome.
In many separation processes(e.g.,extractive distillation,absorption,liquid–liquid extraction,etc.),a third solvent(namely separating agent or entrainer)is commonly needed to add into the mixtures to be separated so ...
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In many separation processes(e.g.,extractive distillation,absorption,liquid–liquid extraction,etc.),a third solvent(namely separating agent or entrainer)is commonly needed to add into the mixtures to be separated so as to improve the separation ***,the selection of a suitable separating agent is the key to ensuring an effective and economical separation processes.
Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to ...
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Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:Laricio pine(Pinus nigra ***),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata ***),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(Larix kaempferi(Lamb.)Carr.)which diff erentiates between 2 visual classes,MEG-1 and *** strength values were calculated for each class(fk,MEG-1=31.80 MPa,f k,MEG-2=24.55 MPa),mean module of elasticity(E 0,mean,MEG-1=13,082 MPA,E 0,mean,MEG-2=12,320 MPA)and density(ρk,MEG-1=456.6 kg m−3,ρk,MEG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MEG-1,and a strength class of C24 to visual class MEG-2.
In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to vi...
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In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 (4): 468-476, 2011].
As photovoltaic energy increasingly penetrates in power systems,transmission system operators have started to request its participation in providing ancillary *** of the demanded services is the power ramp-rate contro...
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As photovoltaic energy increasingly penetrates in power systems,transmission system operators have started to request its participation in providing ancillary *** of the demanded services is the power ramp-rate control(PRRC),which attempts to limit the power ramps produced by intermittent irradiance *** order to achieve the desired objective,solutions based on storage systems or modifying the maximum power point tracking(MPPT)in perturb and observe(P&O)algorithms are commonly *** starting point in PRRC is the determination of the instantaneous power ramprate,and different methods have been proposed in the literature for its ***,the accuracy and computational speed of existing procedures can be improved,which may be critical in situations with rapid irradiance *** this paper,a decoupled photovoltaic power ramp-rate calculation method is presented,in which the effect of variable irradiance and the P&O algorithm are computed *** proposed method has been theoretically demonstrated and tested through simulation and experimental *** results show that it can improve the previous methods in terms of accuracy and computation *** validation with hardware-inthe-loop demonstrates the suitability of the proposed method for real-time applications,even in presence of noisy measurements.
In this essay I will use the expression New Worldism to refer to a particular representation of the New World,developed in Europe.I will take some theories related to this expression(theories of lack and acclimatizati...
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In this essay I will use the expression New Worldism to refer to a particular representation of the New World,developed in Europe.I will take some theories related to this expression(theories of lack and acclimatization)to provide a short introduction to them,taking into special consideration their connection to comparatism as it was developed in 19th-century Brazil.
Aim:To describe findings when comparing lympho-SPECT-CT images before and after lymphovenous anastomosis(LVA)surgeries and to correlate these results with pre-and post-operative volume changes in the limbs of ***:An o...
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Aim:To describe findings when comparing lympho-SPECT-CT images before and after lymphovenous anastomosis(LVA)surgeries and to correlate these results with pre-and post-operative volume changes in the limbs of ***:An observational,prospective,longitudinal study was designed.20 consecutive patients were treated for lymphedema by means of LVA between 2015 and *** were affected by secondary lymphedema(ISGⅡ-Ⅲ)following lymphadenectomy,radiation or *** patients received preoperative rehabilitation as well as radiotherapy after oncological *** volume was measured before surgery and at one year *** was performed under general anesthesia with ICG *** was also used to evaluate postoperative ***-SPECT-CT was performed in all subjects at their first consultation and at one year after every surgical *** of findings included an absence of lymph nodes,new lymph node activity in anatomical areas and new lymphatic activity in extra-anatomical ***:Limb volume decreased in 19 patients after *** patients showed preoperative linear ICG patterns,combined with areas presenting with another type of *** LVA,the linear pattern was observed in 11 ***-CT/lymphoscintigraphy before surgery showed a total absence of lymph nodes,except in two cases,in whom small nodes in anatomical locations were *** LVA,we observed new landmarks in 16 patients corresponding to lymphatic circulation that was not present in preoperative *** six cases,newlymphatic activity compatible with lymph nodes was detectable after *** Spearman correlation coefficient was negative when circumferences and lympho-SPECT-CT were tested(P=0.02).Conclusion:Results showed a postoperative decrease in volume that correlated inversely with lympho-SPECT/CT ***-SPECT/CT provided additional information related to accurate identification and the anatomical location of lymphatic structures that
Noble metal nanoparticles illuminated at their plasmonic resonance wavelength turn into heat *** phenomenon has prompted the development of numerous applications in science and *** optical manipulation of such resonan...
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Noble metal nanoparticles illuminated at their plasmonic resonance wavelength turn into heat *** phenomenon has prompted the development of numerous applications in science and *** optical manipulation of such resonant nanoparticles could certainly extend the functionality and potential applications of optothermal *** this article,we experimentally demonstrate optical transport of single and multiple resonant nanoparticles(colloidal gold spheres of radius 200 nm)directed by tailored transverse phase-gradient forces propelling them around a 2D optical *** show how the phase-gradient force can be designed to efficiently change the speed of the *** have found that multiple hot nanoparticles assemble in the form of a quasi-stable group whose motion around the laser trap is also controlled by such optical propulsion *** assembly experiences a significant increase in the local temperature,which creates an optothermal convective fluid flow dragging tracer particles into the ***,the created assembly is a moving heat source controlled by the propulsion force,enabling indirect control of fluid flows as a micro-optofluidic *** existence of these flows,probably caused by the temperature-induced Marangoni effect at the liquid water/superheated water interface,is confirmed by tracking free tracer particles migrating towards the *** propose a straightforward method to control the assembly size,and therefore its temperature,by using a nonuniform optical propelling force that induces the splitting or merging of the group of *** envision further development of microscale optofluidic tools based on these achievements.
Innovation in products and services is seen by scholars,by specialized media in management,and by some managers as the main currency in modern *** is because it allows high average market profits,fame for innovators,o...
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Innovation in products and services is seen by scholars,by specialized media in management,and by some managers as the main currency in modern *** is because it allows high average market profits,fame for innovators,or brand growth,for ***,in practice,most managers still treat innovation as a secondary issue on their *** problem results from the inability of market professionals to analyze people inside and outside their *** is not possible to develop innovative products in a systematic way without treating this point ***,in this process,creativity is a necessary,but not necessarily sufficient,condition to be fulfilled and requires behavioral *** this context,it is believed that behavioral economics can make a sufficient contribution in the form of an analytical marketing tool by offering an analysis closer to human beings'reality,and,thus,allow a better understanding of people's behavior in the process of innovation in the market.
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