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The nonlinear mechanism in the self-sustaining process (SSP) of wall-bounded turbulence is investigated. Resolvent analysis is used to identify the principal forcing mode that produces the maximum amplification of the velocities in numerical simulations of the minimal channel for the buffer layer and a modified logarithmic (log) layer. The wavenumbers targeted in this study are those of the fundamental mode, which is infinitely long in the streamwise direction and once-periodic in the spanwise direction. The identified mode is then projected out from the nonlinear term of the Navier–Stokes equations at each time step from the simulation of the corresponding minimal channel. The results show that the removal of the principal forcing mode of the fundamental wavenumber can inhibit turbulence in both the buffer and log layer, with the effect being greater in the buffer layer. Removing other modes instead of the principal mode of the fundamental wavenumber only marginally affects the flow. Closer inspection of the dyadic interactions in the nonlinear term shows that contributions to the principal forcing mode come from a limited set of wavenumber interactions. Using conditional averaging, the flow structures that are responsible for generating the nonlinear interaction to self-sustain turbulence are identified as spanwise rolls interacting with oblique streaks. This method, based on the equations of motion, validates the similarities in the SSP of the buffer and log layer, and characterises the underlying quadratic interactions in the SSP of the minimal channel.
The preservation of Military Macaw Ara militaris in Mexico required the implementation of a nationwide assessment evaluating its vulnerability using IUCN criteria. With the combined effort of several institutions, the abundance, location, dispersion, habitat availability, and climatic conditions of areas occupied by the species were determined. Although the species’ extent of occurrence is extensive (263,919 km2) only 29% of this constitutes area of occupancy. Published estimates indicate a series of isolated populations containing from four macaws to 215. Macaws occurred in 35 populations in four regions of 16 states containing an estimated 1,563–3,263 macaws; lower than required for long-term viability. Within regions, neighbouring populations were separated by an average of 68 km. The extent of occurrence is heterogeneous, and macaws inhabit areas that differ in elevation, precipitation, temperature, and forest cover. Higher local abundances occur in landscapes where annual precipitation is ≥1,100 mm, and primary forest availability ≥1,800 km2. Although the existence of undetected macaw groups in Mexico is possible, these are likely to contain only small numbers of individuals, as most detected areas with macaws contain less than 40 individuals, and larger concentrations are more likely to be noticed due to their conspicuous behaviour. The species is threatened primarily by its low overall abundance, fragmented distribution, and forest loss around populations with the highest abundance. With the information generated, it is possible to design and implement specific management and conservation strategies at different geographic scales for the recovery and maintenance of the species in Mexico. It is necessary to strengthen collaborative programmes among conservation organizations, government agencies, and local communities in each region of the country to organize and finance community-based actions such as monitoring, habitat restoration, protection from poaching and the creation of a network of conservation corridors and macaw reserves focused on conservation.
We consider two important extensions of the classical and classical discrete orthogonal polynomials: namely, Krall and exceptional polynomials. We also explore the relationship between both extensions and how they can be used to expand the Askey tableau.
One of the most important prognostic factors in patients diagnosed with schizophrenia is the number of hospitalizations they need during their life. In this work we describe risk factors which determinate psychotic relapse.
Retrospective review of the clinical histories of patients diagnosed with schizophrenia who needed hospitalization during the year 2008 using Hospital Ramon Cajal's history software. Data were analyzed using the SPSS software 15.0 version.
- Socio-demographic: We collected a total of 57 patients, 60% were men and 77,2% were single who lived with their families. 52,8% only had Primary education and 14% had been to University. 38,6% were pensioner and 12,3% workers.
- Risk factors: 54,4% had abandoned their medication, 7% had had recent modifications in their medication, and 35,1% received long acting antipsychotic. 42,1% were identified as substance users.
- 40,4% had been diagnosed with schizophrenia more than three years ago; 57,9% had had less than 3 previous hospitalizations, and 54,4% need hospitalization the previous year.
Male under 30 years old have more risk of needing more hospitalizations. The main risk factor for suffering new psychotic episodes is the medication nonadherence, modifying medication only causes new episodes in few patients. Patients receiving long-acting antipsychotic agents suffer less psychotic relapse. Substance abuse among schizophrenia patients is a major complicating factor since almost half of the hospitalizations are related to it.
To describe the relation of psychosocial factors of care (phase illness, years of care, free time, extra help and symptoms of depression) influence the care burden of dementia family caregivers. To measure the relation of the level of depressive symptoms on an intense level of burden of the dementia family caregivers.
Is selected a sample of 102 primary caregivers by criteria of inclusion to which a surveys do to those that the following information gathered: sociodemographic dates of the caregivers and of the dementia patients, care burden (Zarit Interview) and depressive symptoms (Beck Depression Inventory) of the family caregivers.
Most of the sample experiences an intense burden level (74%) opposite to a light level (26%). Psychosocial characteristics are as per statistics significant in increasing the care burden there were free time, extra help and presence of symptoms of depression. Presence of serious symptoms of depression on the intense burden level are differently front or those who had a minor burden, 22% and 5% respectively.
There are most of the daughter-father/mother and spouse-spouse caregiver couples with a high percentage of caregivers of feminine sex (as in most of the studies realized on caregiver of dependent persons at European and international level). The need for free time and psychic self-care are cost-effective strategies to prevent the depressive disorders, as well as, to improve their caregiver's work. The psychoeducation programs that have being realized at European level directed to family caregiver are necessary in our country.
Natural polyamines (putrescine, spermidine and spermine) are low molecular weight highly protonated aliphatic molecules that physiologically modulate NMDA, AMPA/kainate glutamatergic receptors and limbic dopaminergic neurotransmission. Previous studies had demonstrated that polyamine metabolism might be disrupted in schizophrenia, what could potentially be linked to glutamatergic dysfunction. In particular, polyamine levels in blood and fibroblast cultures from patients with schizophrenia had previously been found to be higher than in healthy controls. Indeed, a significant positive correlation between blood polyamine levels and severity of illness may exist.
In order to test potential differences in blood polyamine levels between drug-free schizophrenia in-patients (n = 12), and healthy controls (n = 26, blood donors), spermidine (spd), spermine (spm), and spermidine/spermine index (spd/spm) were determined using HPLC after dansylation.
No significant differences were found between groups (t = 0,974; df = 36; P = 0,337 for spd, t = l0, 52; df = 36; P = 0,959 for Spm, and, t = 0, 662; df = 36; P = 0,512 for spd/spm).
Though we couldn’t replicate previous findings suggesting disturbances in blood polyamine levels in schizophrenia, this issue may be a promising target. Future research should take into account possible factors such as sex, nutritional state, and stress.
The request of diagnostic imagining techniques, such as CT, is sometimes necessary when working in the emergency service as a psychiatrist. Common circumstances that need CT are altered level of consciousness, absence of psychiatric history, sudden beginning of the symptoms or visual hallucinations.
To study the profitability of the cranial CT for patients with psychiatric symptoms in the Emergency Service.
Retrospective review of the cranial CT was made to patients who presented psychiatric symptoms in the Emergency Service of our hospital from November 2009 to July 2010 using Hospital Ramon Cajal’s history software.
We collected a total of 94 patients.-Sex: there were no important differences, 45,7% were women and 53,3% were men. -Age: < 18 years (3,2%), 18–30 years (12,8%), 31–40 (7,4%), 41–50 (26,6%), 51–60 (17%), 61–70 (14,9%), >71 (18,1%) Cause of consulting: The most frequent cause of consulting was “behavior disorder” (35,1%) and psychotic symptoms (14,9%). Other causes were altered level of consciousness and neurological symptoms.
Image findings: It stands out that up to a 63,8% of the patients had no significant radiological findings. The most frequent diagnosis (26,6%) was cortical-subcortical atrophy, followed by vascular cerebral illness in 9,6%.
Diagnosis: 20,2% were diagnosticated of psychotic disorder, 11,7% neurological disorder and 10,6% dementia.
- Only in 6,4% of the cases the image results were indispensable to reach a correct diagnosis.
- Cranial CT requests should not be made routinely and guides should be followed more strictly.
Violence against health professionals impacts both on the individual and on healthcare systems. Almost 25% of workplace violence belongs to the health sector. In 2001-2002, UK registered 14 incidents per month per 1,000 healthcare workers. In Spain, one third of physicians reported in 2004 having experienced a violent episode during his career. In a study in 2006, 11% of healthcare professionals suffered physical assaults and 64% psychological violence (26.9% and 51.6% respectively at Psychiatric Services), but only a 3.7% of physical assaults and no cases of threats or insults were officially reported.
Rates of complaints are alarmingly low, which requires a comprehensive approach. The UK launched in 1999 the “Zero Tolerance Zone Campaign” and reported incidents increased substantially, with a reverse trend in their severity.
Many prevention plans, records, training courses and awareness campaigns have been developed in Spain and the Supreme Court started considering the assault on a public health professional as a “crime of assault of a public official” in 2007, which increased the penalty. The Unit for Violence Against Physicians (UVAP) was created in Catalonia by Barcelona’s College of Physicians in 2010, and gives comprehensive advice to doctors. The UVAP handles 3-4 incidents per month, mainly of low-level violence and UVAP actions ranges from legal or security advice to legal action against the aggressor. Cases handled by the UVAP represent only the tip of the iceberg, but a short survey among physicians suggest that the mere existence of the unit decreases increases the feeling of safety.
Parasomnias are a category of sleep disorders in which abnormal events occur during sleep, due to inappropriately timed activation of physiological systems.
we report the case of a 41-year-old female who has no psychiatric history. The patient went to emergency department because when she was starting to sleep, in the first state of sleep, she felts a sensation of paralysis in all her body, with incapacity for breathing, chest oppression and tactile hallucinations like something or someone was touching her entire body. Due to that, the patient awoke frightened, with high levels of anxiety, with heart palpitations, shortness of breath, trembling, choking feeling, sweating, nausea and fear of dying. When the patient arrived to the emergency department, she was suffering a panic attack, thinking that she could have some kind of neurological disease or she was suffering a heart attack. after treating the panic attack with 1 mg of lorazepam, all the symptoms subsided gradually.
in this case report, we present a patient with a new-onset parasomnia, with hypnagogic hallucinations and a panic attack at the awakening. It is known that stress factors are closely associated with parasomnias, as we can see in this case because the patient was moving and she was sleeping in a new place.
Parasomnias are very frequently present in general population and they can trigger intense anxiety status that can lead to panic attacks.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
An active region filament in the upper chromosphere is studied using spectropolarimetric data in He i 10830 Å from the GREGOR telescope. A Milne-Eddingon based inversion of the Unno-Rachkovsky equations is used to retrieve the velocity and the magnetic field vector of the region. The plasma velocity reaches supersonic values closer to the feet of the filament barbs and coexist with a slow velocity component. Such supersonic velocities result from the acceleration of the plasma as it drains from the filament spine through the barbs. The line-of-sight magnetic fields have strengths below 200 G in the filament spine and in the filament barbs where fast downflows are located, their strengths range between 100 - 700 G.
The chronology of the Inca Empire has traditionally relied on ethnohistoric dates, which suggest that a northern expansion into modern Ecuador began in AD 1463 and a southern expansion into modern Argentina began in AD 1471. We test the validity of these dates with two Bayesian models, which show that the ethnohistoric dates are incorrect and that the southern expansion began before the northern one. The first model of seven dates shows that the site of Chamical, Ecuador, was first occupied cal AD 1410–1480 (95% probability) and has a high probability of being built prior to the ethnohistoric date. The second is an outlier model of 26 14C dates and 19 thermoluminescence (TL) dates from 10 sites along the empire’s southeastern limit in northwestern Mendoza, Argentina. Here, the Inca occupation began cal AD 1350–1440 (95% probability), also earlier than the ethnohistoric date. The model also suggests that the Inca occupation of Mendoza lasted 70–230 yr (95% probability), longer than previously thought, which calls for new perspectives on the timing and nature of Inca conquests and relationships with local groups. Based on these results, we argue it is time to abandon the traditional chronology in favor of Inca chronologies based on Bayesian models.
This work shows the electrochemical study of nickel (Ni) and TiC/Ni composite immersed in synthetic seawater. In order to characterize the corrosion process, polarization curves (PC) were carried out. All electrochemical measures were made under static conditions, room temperature, atmospheric pressure and 24 hours exposure time. An electrochemical cell with a typical three-electrode array was used. Effect of TiC as reinforcement into the Ni matrix was evaluated. According PC results, it is possible to point out that the corrosion rate (CR) of the TiC/Ni composite was higher than Ni corrosion rate. The obtained results indicate that the corrosion process of both materials is of mixed type, that is to say a process of transfer of load influenced by a mechanism of mass transfer. Observations through scanning electron microscopy (SEM) revealed that mechanism of corrosion was cells of differential aeration (difference of concentration of oxygen). The corrosion morphology was localized type (pits and crevice).
The perspective of statistical state dynamics (SSD) has recently been applied to the study of mechanisms underlying turbulence in a variety of physical systems. An SSD is a dynamical system that evolves a representation of the statistical state of the system. An example of an SSD is the second-order cumulant closure referred to as stochastic structural stability theory (S3T), which has provided insight into the dynamics of wall turbulence, and specifically the emergence and maintenance of the roll/streak structure. S3T comprises a coupled set of equations for the streamwise mean and perturbation covariance, in which nonlinear interactions among the perturbations has been removed, restricting nonlinearity in the dynamics to that of the mean equation and the interaction between the mean and perturbation covariance. In this work, this quasi-linear restriction of the dynamics is used to study the structure and dynamics of turbulence in plane Poiseuille flow at moderately high Reynolds numbers in a closely related dynamical system, referred to as the restricted nonlinear (RNL) system. Simulations using this RNL system reveal that the essential features of wall-turbulence dynamics are retained. Consistent with previous analyses based on the S3T version of SSD, the RNL system spontaneously limits the support of its turbulence to a small set of streamwise Fourier components, giving rise to a naturally minimal representation of its turbulence dynamics. Although greatly simplified, this RNL turbulence exhibits natural-looking structures and statistics, albeit with quantitative differences from those in direct numerical simulations (DNS) of the full equations. Surprisingly, even when further truncation of the perturbation support to a single streamwise component is imposed, the RNL system continues to self-sustain turbulence with qualitatively realistic structure and dynamic properties. RNL turbulence at the Reynolds numbers studied is dominated by the roll/streak structure in the buffer layer and similar very large-scale structure (VLSM) in the outer layer. In this work, diagnostics of the structure, spectrum and energetics of RNL and DNS turbulence are used to demonstrate that the roll/streak dynamics supporting the turbulence in the buffer and logarithmic layer is essentially similar in RNL and DNS.
The invariants of the velocity gradient tensor,
, and their enstrophy and strain components are studied in the logarithmic layer of an incompressible turbulent channel flow. The velocities are filtered in the three spatial directions and the results are analysed at different scales. We show that the
plane does not capture the changes undergone by the flow as the filter width increases, and that the enstrophy/enstrophy-production and strain/strain-production planes represent better choices. We also show that the conditional mean trajectories may differ significantly from the instantaneous behaviour of the flow since they are the result of an averaging process where the mean is 3–5 times smaller than the corresponding standard deviation. The orbital periods in the
plane are shown to be independent of the intensity of the events, and of the same order of magnitude as those in the enstrophy/enstrophy-production and strain/strain-production planes. Our final goal is to test whether the dynamics of the flow is self-similar in the inertial range, and the answer turns out to be that it is not. The mean shear is found to be responsible for the absence of self-similarity and progressively controls the dynamics of the eddies observed as the filter width increases. However, a self-similar behaviour emerges when the calculations are repeated for the fluctuating velocity gradient tensor. Finally, the turbulent cascade in terms of vortex stretching is considered by computing the alignment of the vorticity at a given scale with the strain at a different one. These results generally support a non-negligible role of the phenomenological energy-cascade model formulated in terms of vortex stretching.
This article provides a thematic overview of a subset of controversial officer involved shootings that have occurred in Denver, Colorado during a period of thirty years (1983-2012). Determining whether a shooting was legally justified involved multiple participants, including local, national, and international representatives. The primary stakeholders were City and County District Attorneys regarding whether to file criminal charges against the officer, and Managers of Safety for whether officers acted within police departmental policy. Although most cases were processed without conflict, a small number were challenged by members of the community based on thematic reasons of shooting individuals who had not committed a crime, violating continuum of force standards, and entrusting law enforcement officers with the power to use deadly force both off-duty and while working secondary jobs. Despite outcome legitimacy vested in a small number of public officials, community members often reported a lack of justice and accountability. They struggled to get public officials to take notice and implement systematic change. Reviewing controversial shootings highlights the multiple issues involved in protecting law enforcement officers from encountering criminal charges, and in essence the procurement of colonial control. Critical Race Theory (interest convergence and storytelling), Social Dominance Theory, along with the historical framework of W. E. B. Du Bois, were utilized to explore a number of officer-involved shootings that continue to produce disparate outcomes by race, class, and gender.
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
In a 1-year survey at a university hospital we found that 20·6% (81/392) of patients with antibiotic associated diarrohea where positive for C. difficile. The most common PCR ribotypes were 012 (14·8%), 027 (12·3%), 046 (12·3%) and 014/020 (9·9). The incidence rate was 2·6 cases of C. difficile infection for every 1000 outpatients.
Year 2 findings are reported from a longitudinal, experimental-control study involving 31 Spanish-speaking preschoolers (aged 38–48 months) randomly assigned to two Head Start classrooms. In Year 1, classrooms differed only in the language of instruction, with teachers using only Spanish in one classroom and only English in the other. In Year 2, an experimental transitional bilingual education (TBE) model was implemented, with English being gradually introduced in the TBE classroom until a ratio of 30:70 English-to-Spanish was achieved and Spanish being gradually introduced in the predominantly English (PE) classroom until a ratio of 70:30 English-to-Spanish was achieved. Year 2 results were consistent with Year 1, with the TBE classroom exceeding the PE classroom on all Spanish measures of language and literacy development and no significant differences favoring the PE classroom. Results also indicated that Year 2 trajectories were conditional on first-year effects, suggesting that sustained growth in dual language learner's early literacy may depend on early intervention among 3-year-old preschoolers.