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Ride-hailing (or ride-sharing) companies are continuing to penetrate through the market of transportation-for-hire services in major metropolitan cities all across the globe, with an endless pursuit to revolutionize travel and redefine the taxicab industry. Since the fall of 2015 Las Vegas, Nevada is another city that has recently been added to the ever growing list of Uber- and Lyft-enabled metropolises. With such Ride-hailing Companies (RHCs) being introduced to cities whose economy is predominately built on the foundations of tourism, questions have inevitably mounted as to the impacts such new services are having on the transportation system, in particular, the taxicab industry. Services such as Uber and Lyft are competing with the taxicab industry for users within the resort corridor and across the valley. This study proposes a multinomial linear regression analysis using a multi-modal time-series travel dataset from Las Vegas to capture the impacts of RHCs on taxicab ridership. After controlling for a number of explanatory variables, including total number of monthly visitors, transit ridership, and several other economic indicators, the results show that RHCs do in fact have a negative (and significant) impact on taxicab ridership. A perhaps counterintuitive finding is that transit ridership actually complements (instead of competes directly with) taxi ridership, which could have significant implications moving forward. This study aims to shed even more light on the growing market of RHCs, with an attempt to estimate and quantify observed impacts in Las Vegas, Nevada, and provide transportation agencies, jurisdictions, stakeholders, and policy- and decision-makers across the nation with tangible evidence that may help guide and steer their transportation planning and investment efforts.

Wastewater reuse for agriculture is common worldwide; wastewater treatment, however, is rare in many countries, leading to high potential for exposure to harmful pathogens. Mexico City, one of the largest producers of untreated wastewater for agricultural use worldwide, was the site of key epidemiologic studies conducted in the 1990s. We both reviewed the literature on and conducted a cross-sectional study of diarrheal risk and wastewater contamination to provide an updated assessment of health risks and to inform an upcoming update of the 2006 WHO guidelines on wastewater reuse. We surveyed communities in the Mezquital Valley that use wastewater for irrigation and communities that use well water to compare the prevalence of self-reported diarrheal disease in children under five years old. Wastewater, well water, household environmental samples, and stool samples were collected and analyzed. Communities exposed to wastewater had a higher one-week prevalence of diarrhea (10%) compared to unexposed communities (5%). This association remained in an adjusted modified Poisson regression model (PR = 2.31, 95% CI 1.00, 5.31), but not when limited to households engaged in agriculture. Water quality indicators document differences between irrigation water from the two community groups. These results are in agreement with 25 population studies identified by our review that were conducted since or not included in the 2006 WHO guidelines and show consistent negative impacts of wastewater exposure on health. While overall diarrheal prevalence has declined when compared to studies conducted over 25 years ago in the same region, the association of diarrheal disease and wastewater exposure has remained and possibly increased. With rising urbanization worldwide, attention to these risks and wastewater treatment is becoming increasingly important.

Let ( φ t ) , ( ϕ t ) be two one-parameter semigroups of holomorphic self-maps of the unit disk D ⊂ C . Let f : D → D be a homeomorphism. We prove that, if f ∘ ϕ t = φ t ∘ f for all t ≥ 0 , then f extends to a homeomorphism of D ‾ outside exceptional maximal contact arcs (in particular, for elliptic semigroups, f extends to a homeomorphism of D ‾ ). Using this result, we study topological invariants for one-parameter semigroups of holomorphic self-maps of the unit disk.

We prove that topological evolution families on a Riemann surface S are rather trivial unless S is conformally equivalent to the unit disc or the punctuated unit disc. We also prove that, except for the torus where there is no non-trivial continuous Loewner chain, there is a topological evolution family associated to any topological Loewner chain and, conversely, any topological evolution family comes from a topological Loewner chain on the same Riemann surface.

The purpose of this paper is to evaluate the effect of five strains of Metarhizium anisopliae (Ma) and three strains of Isaria fumosorosea (Ifr) at a concentration of 1 × 108 colony forming units/ml applied by spraying onto bovines with controlled infestation of Haematobia irritans under stable conditions in the Mexican dry tropics. Four experiments were performed, in each of which three treatments (two fungal strains and one control) were evaluated with eight repetitions for each one, by carrying out a single application of the aqueous suspension of each strain. The animals were isolated in individual cages and direct counts of the infestation were carried out for 13 days. It was observed that strains Ma2, Ma6, Ma10, Ma14, and Ma34 caused 94–100% reduction in infestation between days 12 and 13 post-treatment, while strains Ifr19, Ifr11, and Ifr12 reduced infestation from 90% to 98% up to day 13 post-application. There was an effect in the generation of horn flies from the excrement of bovines that were treated with different strains, reducing the reproduction of subsequent generations. It was concluded that the strains of M. anisopliae and I. fumosorosea evaluated in this study can be used as biocontrol agents in infestations of H. irritans in stabled bovines.

We obtain exhaustive results and treat in a unified way the question of boundedness, compactness, and weak compactness of composition operators from the Bloch space into any space from a large family of conformally invariant spaces that includes the classical spaces like $BMOA$, $Q_\alpha$, and analytic Besov spaces $B^p$. In particular, by combining techniques from both complex and functional analysis, we prove that in this setting weak compactness is equivalent to compactness. For the operators into the corresponding "small" spaces we also characterize the boundedness and show that it is equivalent to compactness., Comment: 27 pages

We show that there is a proper boundary Denjoy–Wolff theorem for those parabolic self-maps of D of zero hyperbolic step whose Koenigs function has an angular limit almost everywhere on ∂ D . We also provide some quantitative information about this convergence.

We extend previous transport calculations performed on a single-electron transistor (SET) based upon a semiconductor quantum dot (QD) doped with a single Mn ion (which behaves as a quantum nanomagnet) by calculating the stationary fluctuations of the current, or shot noise, of hole transport through the SET. Our results show that the zero-frequency shot noise is determined by the magnetic state of the QD. In particular, we find super-Poissonian noise in a region of bias and gate voltages where the competing dynamics between slow and fast channels results in bunching.

In this paper we study when two finite Blaschke products commute. We complete previous results by Chalendar and Mortini (when they have a fixed point in the unit disk) and by Arteaga (when they do not have a fixed point in the unit disk).

We give a complete classification up to conjugation of continuous semigroups of linear fractional self-maps of the unit ball.

Fundamento El tabaquismo es un claro factor de riesgo aterogenico en adultos. El objetivo de este estudio, subestudio del estudio multinacional de necropsias PBDAY, fue evaluar el impacto del tabaquismo como factor de riesgo aterogenico en ninos y jovenes de entre 5 y 34 anos de edad fallecidos accidentalmente durante los anos 1986-1996 Material y metodos Del centro de coordinacion general del PBDAY en Malmo se recibieron en el Centro de Investigaciones y Referencias de Aterosclerosis de La Habana un total de 966 muestras de la mitad izquierda de la aorta toracica, 947 de la mitad izquierda de la aorta abdominal y 959 de la arteria coronaria derecha. Las arterias procedieron de 11 paises localizados en America, Africa, Europa, sudeste asiatico y sudoeste asiatico. Las arterias se procesaron utilizando el sistema aterometrico para la caracterizacion patomorfologica y morfometrica de la lesion aterosclerotica. El antecedente de tabaquismo se recogio por interrogatorio a los allegados de los individuos fallecidos, y la poblacion de autopsies se dividio en fumadores y no fumadores. Los datos se procesaron utilizando analisis estadisticos descriptivos, comparativos y multivariado Resultados La distribucion de estrias adiposas y placas fibrosas en las tres arterias estudiadas, aorta toracica, aorta abdominal y coronaria derecha, fue mayor en los fumadores que en los no fumadores. La transformacion de estrias adiposas en placas fibrosas comenzo mas temprano y con mayor intensidad en los fumadores. Las lesiones en las tres arterias presentaron diferencias significativas entre fumadores y no fumadores por analisis MANOVA. Por analisis ANOVA, la superficie intimal ocupada por estrias adiposas en la aorta toracica, por estas y las placas fibrosas en la aorta abdominal, y por las placas fibrosas en la coronaria derecha era significativamente mas alta en los fumadores que en los no fumadores Conclusiones En este estudio se demuestra claramente que el tabaquismo es un fuerte factor de riesgo de aterosclerosis en edades tempranas

Methods: The seven partnering states are: IN, KS, ND, OH, SD, and WI. Active Community Coalitions (14) from 7 Intervention and 7 Comparison communities plus 7 Community Coaches (Intervention communities only) completed community assessments prior to implementing an annually selected intervention impacting nutrition and physical activity. A Toolkit of evidence based/informed resources was drafted for their initial use.

Let ϕ, ψ be analytic functions defined on D, such that ϕ(D) ⊆ D. The operator given by f ↦ ψ(f ∘ ϕ) is called a weighted composition operator. In this paper we deal with the boundedness, compactness, weak compactness, and complete continuity of weighted composition operators on Hardy spaces Hp (1 ≤ p < ∞). In particular, we prove that such an operator is compact on H1 if and only if it is weakly compact on this space. This result depends on a technique which passes the weak compactness from an operator T to operators dominated in norm by T.

Oscillatory patterns in neocortical electrical activity show various degrees of large-scale synchrony depending on experimental conditions, but the exact mechanisms underlying these variations of coherence are not known. Analysis of multisite local field potentials revealed that the coherence of spindle oscillations varied during different states. During natural sleep, the coherence was remarkably high over cortical distances of several millimeters, but could be disrupted by artificial cortical depression, similar to the effect of barbiturates. Possible mechanisms for these variations of coherence were investigated by computational models of interacting cortical and thalamic neurons, including their intrinsic firing patterns and various synaptic receptors present in the circuitry. The model indicates that modulation of the excitability of the cortex can affect spatiotemporal coherence with no change in the thalamus. The highest level of coherence was obtained by enhancing the excitability of cortical pyramidal cells, simulating the action of neuromodulators such as acetylcholine and noradrenaline. The underlying mechanism was due to cortex-thalamus-cortex loops in which a more excitable cortical network generated a more powerful and coherent feedback onto the thalamus, resulting in highly coherent oscillations, similar to the properties measured during natural sleep. In conclusion, these experiments and models are compatible with a powerful role for the cortex in triggering and synchronizing oscillations generated in the thalamus, through corticothalamic feedback projections. The model suggests that intracortical mechanisms may be responsible for synchronizing oscillations over cortical distances of several millimeters through cortex-thalamus-cortex loops, thus providing a possible cellular mechanism to explain the genesis of large-scale coherent oscillations in the thalamocortical system.

Spindling activity characterizes the EEG of animals and humans in the early stages of resting sleep. Spindles are defined as waxing and waning rhythmic waves at 7‐14 Hz that recur periodically every 3‐10 s. Spindling originates in the thalamus, 7 but a role for

We have investigated the degree of synchronization between cortical, thalamic reticular and thalamocortical neurons of cats during low-frequency (< 15 Hz) sleep-like oscillations, as they appear under anaesthesia. We have also studied the effects exerted by cortical stimulation on the synchronization among thalamic units. Parallel experiments [Steriade et al. (1996) J. Neurosci. 16, 392-417] in this laboratory have demonstrated the similarity between the slow oscillation (< 1 Hz) under ketamine-xylazine anaesthesia and that occurring during the natural state of resting sleep. Spontaneous activity was recorded simultaneously, with independent microelectrodes, from groups of two to five physiologically identified neurons. The rhythmicity of spontaneous activity and the temporal relations between cellular discharges were statistically evaluated by auto- and crosscorrelation techniques. We have found no topography in the distribution of synchronization between thalamic reticular and thalamocortical cells. Only the slow, cortical-generated oscillation (< 1 Hz) displayed a stable frequency and correlation among groups of cortical and thalamic cells. The other two sleep oscillations (thalamic-generated spindles at 7-14 Hz and clock-like delta at 1-4 Hz) fluctuated in frequency and the degree of correlation between neurons varied. Cortical volleys entrained and synchronized thalamic cells, and triggered synchronized spindling in the thalamus. These results extend for large populations of cortical and thalamic neurons the phase relations found in intracellular recordings.

We have studied the variations in the degree of correlated firing within the low-frequency sleep rhythms (15 Hz) between cortical, thalamic reticular and thalamocortical neurons during changes in the amplitude and frequency of brain electrical activity in anaesthetized cats. Extracellular discharges of neuronal groups of two to five physiologically identified cortical and thalamic units were recorded simultaneously with independent microelectrodes. The firing patterns and the temporal correlation between spike-trains were evaluated by auto- and crosscorrelograms. Although the animals were under deep anaesthesia, additional doses of the same or different anaesthetics were able to alter the electroencephalographic pattern, inducing waves with higher amplitude. Similar transitions occurred spontaneously. We found that the presence of rhythmic behaviour in cells of corticothalamic networks, as well as their degree of correlated firing, was extremely sensitive to even slight alterations in the state of the electroencephalogram. Cells belonging to the same functional system, but located distantly, became highly synchronized upon the increased amplitude of brain waves. Thus, an electroencephalogram characterized by slow waves corresponds to a state of rhythmic and correlated firing among cortical and thalamic neurons. The highly coherent activity during sleep patterns transcends the borders which limit the functioning during the waking brain.

This experimental study on anesthetized cats used intracellular recordings of cortical, thalamocortical and reticular thalamic neurons (n = 54), as well as multi-site extracellular recordings (n = 36), to investigate the cellular correlates of EEG burst-suppression patterns, defined as alternating wave bursts and periods of electrical silence. Burst-suppression was elicited by the administration of the same or other anesthetic agents upon the background of an already synchronized EEG activity. About 95% of cortical cells entered burst-suppression, in close time-relation with EEG activity, displaying sequences of phasic depolarizing events associated with bursts of EEG waves and an electrical silence of the neuronal membrane during flat EEG epochs. The membrane potential (Vm) hyperpolarized by approximately 10 mV prior to any EEG change and the slow rhythms reflecting deep stages of anesthesia progressively disorganized with transition to burst-suppression. During flat EEG epochs, the apparent input resistance (tested through short hyperpolarizing current pulses) decreased (range 12-60%) and neuronal responsiveness to orthodromic volleys (tested by thalamic and cortical evoked excitatory postsynaptic potentials) was dramatically reduced. It is proposed that the decreased input resistance is mainly due to an increase in K+ conductances. At variance with cortical neurons, only 60-70% of thalamic cells ceased firing before overt EEG burst-suppression and were completely silent during flat periods of EEG activity. The remaining 30-40% of thalamic cells discharged rhythmic (1-4 Hz) spike bursts during periods of EEG silence. This rhythm, within the frequency range of delta waves, is generated in thalamic cells by the interplay between two of their intrinsic currents at critical levels of Vm hyperpolarization. However, with the deepening of burst-suppression, when silent EEG periods became longer than 30 sec, thalamic cells also ceased firing. The assumption that full-blown burst-suppression is achieved through virtually complete disconnection in brain circuits implicated in the genesis of the EEG is corroborated by the revival of normal cellular and EEG activities after volleys setting into action thalamic and cortical networks.

The state of resting sleep is associated with a series of oscillations generated in cortical and thalamic networks. A newly discovered rhythm groups the spindle and delta sleep oscillations within slowly recurring (< 1 Hz) sequences. Multi-site, extra- and intracellular recordings provide evidence for synchronization of various classes of cell in the neocortex and thalamus during sleep oscillations that might reach paroxysmal levels similar to epileptic states. Sleep oscillations and the underlying synchronizing processes are disrupted during transition to brain arousal.

Thalamocortical neurons located in the large-celled district of the cat intralaminar centrolateral nucleus were found to discharge spike-bursts with unusually high frequencies (800–1000 Hz) during spindle oscillations of the electroencephalogram. In chronically implanted animals, similar spike-bursts were also fired during wakefulness and rapid eye movement sleep, two behavioral states in which other thalamocortical neurons tonically fire single spikes. Such high-frequency spike-bursts recurred with a fast rhythm of 20–40 Hz during waking and rapid eye movement sleep. Intracellular recordings under barbiturate anesthesia showed that, during spindle oscillations, the spike-bursts of intralaminar neurons are generated by brief low-threshold spikes with a much shorter refractory phase than in other thalamocortical cells. Depolarizing pulses from the resting membrane

Conclusions and Implications: Despite many criticisms, children who eat school lunches eat fewer calories at lunch compared to students who bring lunch from home. Interestingly, though, students who bring lunch from home may be front-loading their calories earlier in the day when compared to NSLP students. Thus student consumption patterns outside of school should be better understood to identify solutions to help reduce childhood obesity. Funding: None