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Introduction: The spread of SARS-CoV-2 cases grew exponentially. In Mexico, it focused mainly on containing the disease and adopting activities and actions to mitigate it. Hospital reconversion was a fundamental strategy in the management of care for patients with COVID-19. Objective: To know the clinical characteristics of patients admitted with respiratory disease and probable COVID-19 in the Zacatecas General Hospital “Luz González Cosío” México. Material and methods: Descriptive, cross-sectional, and analytical study, at the General Hospital, from March 2019 to September 2021; using data from the Respiratory Disease Surveillance System. Data from patients admitted with a diagnosis of some pathology of respiratory disease and probable COVID-19 were analyzed. Results: We included 2,678 diagnosed with respiratory disease and a mean age; of 47.6 ± 21.6 gender distribution was almost equal; women 1,344 (51.0%). positive result to COVID-19 by PCR; 1,654 negatives; 900 and 124 without result. 193 (7.0%) required mechanical ventilation. The presence of comorbidities was evaluated; type 2 diabetes mellitus, systemic arterial hypertension, obesity, alone and together. Also the association of the age factor, as well as the lethality index; was 531 (19.6%). Discussion: What has been published in other studies about comorbidities and their influence on the severity of COVID-19 is confirmed, disagreeing on the case fatality rate; 20.7% against what was reported; 17.6% in other countries for COVID-19 hospitalized. An age variable was used as a risk factor with a cut-off point > 45 years; (FRE), obtaining; RR 3.42 (95% CI 2.79 to 4.19) and an odds ratio of 4.015 in binary logistic regression analysis. Reported male mortality (OR = 1.45; 95% CI: 1.41–1.51) according to our OR results; 1,45. Conclusion: The present study shows how certain chronic diseases influenced respiratory disease to present a serious state, regardless of the positive or negative result of COVID-19.

Classically acute syndesmosis injuries have been treated using screws. A few years ago more flexible implants appeared evolving to current TighRope® Knotless. The primary aim of this study is to compare clinical and radiographic outcome of both implants.From April 2019 to September 2020 68 patients diagnosed with acute syndesmosis injury were randomised to use screws or TighRope® Knotless. Syndesmosis reduction was assessed using bilateral CT potsoperatively. Outcomes were clinically and radiologically assessed at three, six, and twelve months after surgery.No significant differences were identified in the AOFAS Scale between groups at three months (83.1 vs. 81.80; P=1.03), nor at six (88.27 vs. 88; P=.26) or at twelve (93.03 vs. 92.10; P=.93). There were also no differences in Olerud-Molander scale at three (65 vs. 61.50; P=3.5), six (82.33 vs. 80.67; P=1.67) and twelve months (92.67 vs. 90; P=2.67). Likewise, there were no differences in rate of postoperative malreduction (no cases in both groups), loss of reduction (three cases in screw group vs. four in TighRope® Knotless group, P=.54) or complications (P=1).Treatment of acute syndesmosis injuries with screws or the TighRope® Knotless implant is similar in both clinical and radiological results.

Classically acute syndesmosis injuries have been treated using screws. A few years ago more flexible implants appeared evolving to current TighRope® Knotless. The primary aim of this study is to compare clinical and radiographic outcome of both implants.From April 2019 to September 2020 68 patients diagnosed with acute syndesmosis injury were randomized to use screws or TighRope® Knotless. Syndesmosis reduction was assessed using bilateral CT potsoperatively. Outcomes were clinically and radiologically assessed at three, six, and twelve months after surgery.No significant differences were identified in the AOFAS Scale between groups at three months (83.1 vs. 81.80; P=1.03), nor at six (88.27 vs. 88; P=.26) or at twelve (93.03 vs. 92.10; P=,93). There were also no differences in Olerud-Molander scale at three (65 vs. 61.50; P=3.5), six (82.33 vs. 80.67; P=1.67) and twelve months (92.67 vs. 90; P=2.67). Likewise, there were no differences in rate of postoperative malreduction (no cases in both groups), loss of reduction (three cases in screw group vs. four in TighRope® Knotless group, P=.54) or complications (P=1).Treatment of acute syndesmosis injuries with screws or the TighRope® Knotless implant is similar in both clinical and radiological results.

The quality control of medicines guarantees the effectiveness of treatments for diseases. We explore the use of texture analysis of patterns in dried droplets as a tool to readily detect both impurities and changes in drug concentration. Four types of medicines associated with different routes of administration were analyzed: Methotrexate, Ciprofloxacin, Clonazepam, and Budesonide. We use NaCl and a hot substrate at 63 ∘C to promote aggregate formation and to reduce droplet drying time. Depending on the medicine, optical microscopy reveals different complex aggregates such as circular to oval splatters, fern-like islands, crown shapes, crown needle-like and bump-like patterns as well as dendritic branched and star-like crystals. We use some physical features of the stains (as the stain diameter and superficial area) and gray level co-occurrence matrix (GLCM) to characterize patterns of dried droplets. Finally, we show that structural analysis of stains can achieve 95% accuracy in identifying medicines with 30% water dilution, while it achieves 99% accuracy in detecting drugs with 10% other substances.

Rapid diagnosis provides better clinical management of patients, helps control possible outbreaks, and increases survival. The study of deposits produced by the evaporation of droplets is a useful tool in the diagnosis of some health problems. With the aim to improve diagnostic time in clinical practice where we use the evaporation of droplets, we explored the effects of substrate temperature on pattern formation of dried droplets in globular protein solutions. Three deposit groups were observed: “functional” patterns (from 25 to 37 ∘C), “transition” patterns (from 44 to 50 ∘C), and “eye” patterns (from 58 to 63 ∘C). The dried droplets of the first two groups show a ring structure (“coffee-ring”) that confines a great diversity of aggregates such as needle-like structures, tiny blade-shape crystals, highly symmetrical crystallization patterns, and amorphous salt aggregates. In contrast, the “eye” patterns are deposits with a large inner aggregate surrounded by a coffee ring, and they can appear from the evaporation of droplets in protein binary mixtures and blood serum. Interestingly, the unfolding proteins correlates with the formation of “eye” patterns. We measured stain diameter, “coffee-ring” thickness, radial density profile, and entropy computed by GLCM-statistics to quantify the structural differences among deposit groups. We found that “functional” patterns are structurally indistinguishable among them, but they are clearly different from elements of the other deposit groups. An exponential decay function describes pattern formation time as a function of substrate temperature, which is independent from protein concentration. Patterns formation at 32 ∘C takes place up to 63% less time and preserves the structural characteristics of dried droplets in proteins formed at room temperature. Therefore, we argue that droplet evaporation at this substrate temperature could be an excellent candidate to make a more efficient diagnosis based on droplet evaporation of biofluids.

In this work, we study the interplay between intrinsic biochemical noise and the diffusive coupling, in an array of three stochastic Brusselators that present a limit-cycle dynamics. The stochastic dynamics is simulated by means of the Gillespie algorithm. The intensity of the intrinsic biochemical noise is regulated by changing the value of the system volume (Ω), while keeping constant the chemical species' concentration. To characterize the system behavior, we measure the average spike amplitude (ASA), the order parameter R, the average interspike interval (ISI), and the coefficient of variation (CV) for the interspike interval. By analyzing how these measures depend on Ω and the coupling strength, we observe that when the coupling parameter is different from zero, increasing the level of intrinsic noise beyond a given threshold suddenly drives the spike amplitude, SA, to zero and makes ISI increase exponentially. These results provide numerical evidence that amplitude death (AD) takes place via a homoclinic bifurcation.

We have determined a value for the 1S0 neutron-neutron scattering length (ann). The scattering length result is presented for the extended-soft-core (ESC04) interaction. The value obtained in the present work is ann = -18.6249 fm. The method of solution of the radial Schr?dinger equation with nonlocal potential for nucleonnucleon pairs is described and the result is consistent with previous determinations of ann = -18.63 ± 0.10 (statistical) ± 0.44 (systematic) ± 0.30 (theoretical) fm. The nonlocal potentials are of the central, spin-spin, spin-or-bital, and tensor type. The analysis from the ESC04 interaction is done at energies 0 ￡ Tlab ￡ 350 MeV. We compare the present result with experimental S-wave phase shifts analysis and agreement is found.

La liberación proximal de los gemelos se realiza para corregir la retracción de éstos, que puede acompañar a patologías de pie y tobillo en el adulto. En este artículo mostramos una técnica sencilla en la que se libera la cabeza del gemelo medial a través de una mínima incisión.Gastrocnemius release is performed to correct an isolated gastrocnemius tightness that may accompany foot and ankle pathology in the adult. This article shows a simple technique in which the medial head of the gastrocnemius is released through a minimal incision.

Objetivos. La rotura distal del tendon del biceps braquial es una lesion poco frecuente. El objetivo de nuestro estudio es evaluar los resultados de las roturas distales de dicho tendon, intervenido quirurgicamente por via anterior entre noviembre de 1998 y diciembre de 2003. Material y metodo. Estudio retrospectivo con 12 pacientes y 13 lesiones, con un seguimiento medio de 37 meses (12-60). La edad media fue de 37,6 anos, y todos los pacientes eran del sexo masculino. Todas las lesiones se localizaron en el brazo dominante, excepto un caso de rotura bilateral. Todos fueron intervenidos a traves de un abordaje anterior. Diez lesiones (76,9%) se suturaron con arpones, dos (15,4%) con tuneles oseos y una (7,7%) se suturo con un anclaje con endobutton. Todos los pacientes, excepto uno, fueron inmovilizados con una ferula de escayola braquioantebraquial posterior durante las dos primeras semanas postoperatorias. En cinco pacientes se continuo con esta inmovilizacion y en seis se sustituyo por una ortesis articulada. Resultados. Se evaluaron los parametros de: movilidad, fuerza, dolor y satisfaccion personal. Todos los pacientes presentaron una movilidad completa. Once pacientes (91,6%) recuperaron la fuerza totalmente. Como complicaciones se encontro una paresia transitoria del nervio radial. La satisfaccion personal fue excelente en once pacientes (91,6%) y buena en un paciente (8,4%). No existio ninguna nueva re-ruptura. Conclusiones. Los resultados clinicos y funcionales han sido en la mayoria de los pacientes excelentes, por lo que se recomienda la sutura con arpones por via anterior. Palabras clave: rotura, tendon distal del biceps, via anterior, arpones.

Purpose Distal ruptures of the brachial biceps tendon are an infrequent injury. The purpose of this paper is to assess the outcome of distal ruptures of the tendon addressed surgically through an anterior approach between November 1998 and December 2003. Materials and methods Retrospective study of 12 patients and 13 injuries with a mean follow-up of 37 months (range: 12-60). Mean age was 37.6 years and all patients were male. All injuries were located in the dominant arm, except for one case in which the rupture was bilateral. All were operated with an anterior approach. In ten injuries (76.9%) harpoon sutures were used, in two (15.4%) bone tunnels and in one instance (7.7%) an endobutton anchor. All patients but one were immobilized with a brachioantebrachial plaster splint during the first two weeks post-op. In five patients, this immobilization was continued, whereas in four it was replaced by an articulated brace. Results Range of movement, strength, pain and personal satisfaction were the parameters assessed. All patients had full mobility. Eleven patients (91.6%) recovered their full strength. As far as complications are concerned, we had a transient radial nerve palsy. Personal satisfaction was excellent in eleven patients (91.6%) and good in one (8.4%). There was no re-rupture. Conclusions Our clinical and functional results are excellent, for which reason we recommend harpoon suturing with an anterior approach.

We analyzed the two coupled propagation equations in a circularly birefringent fiber. We found that the difference between perpendicular and parallel Raman gain results in energy transform from a slow to fast circularly polarized component. We have shown this effect analytically and by a numerical simulation. We analyzed and measured the polarization of solitons generated by modulation instability and we found that polarization ellipticity of solitons is distributed randomly; however, the ellipticity of polarization is close to the polarization of the input pulse and always is shifted toward the circular polarization. Therefore, if a circularly polarized pulse is launched at the fiber input then the produced solitons are also circularly polarized. In the experiment, we used SMF-28 twisted fiber by 6 turns/m; the fiber twist mitigated the random linear birefringence, and the fiber was pumped by 1-ns pulse. We have found that circular polarization of the pump pulse in the twisted fiber produces circularly polarized solitons with a high grade of polarization while in the fiber without twist the soliton polarization was random.

We present the first measurement of the left-right cross section asymmetry (${\mathit{A}}_{\mathit{L}\mathit{R}}$) for Z boson production by ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$ collisions. The measurement was performed at a center-of-mass energy of 91.55 GeV with the SLD detector at the SLAC Linear Collider which utilized a longitudinally polarized electron beam. The average beam polarization was (22.4\ifmmode\pm\else\textpm\fi{}0.6)%. Using a sample of 10 224 Z decays, we measure ${\mathit{A}}_{\mathit{L}\mathit{R}}$ to be 0.100\ifmmode\pm\else\textpm\fi{}0.044(stat)\ifmmode\pm\else\textpm\fi{}0.004(syst), which determines the effective weak mixing angle to be ${\mathrm{sin}}^{2}$${\mathrm{\ensuremath{\theta}}}_{\mathit{W}}^{\mathit{e}\mathit{f}\mathit{f}}$=0.2378 \ifmmode\pm\else\textpm\fi{}0.0056(stat)\ifmmode\pm\else\textpm\fi{}0.0005(syst).

We argue for the need of mathematical models as integrative tools for understanding processes of cell differentiation and morphogenesis, involving the concerted action of multiple components at different spatiotemporal scales during plant development. We propose dynamical models of gene regulatory networks (GRNs) as the basis for such means. Such models enable the identification of specific steady-state gene expression patterns (attractors), which correspond to different cell types. A comparison between discrete and continuous models is then presented, and we propose that the dynamical structure of a GRN subject to noise conceptually corresponds to Waddington's “epigenetic landscape”. In the third section, we review methods to infer GRN topology from microarray experiments. These include reverse engineering techniques such as Bayesian networks, mutual information, and continuous analysis models. We discuss the application of these approaches to plant cases. However, detailed molecular biology experiments have been very successful in deciphering the structure of underlying small networks. Therefore, we then focus our attention on GRN models of such small modules for various processes of plant development. The first example corresponds to a single-cell GRN for primordial cell specification during early stages of Arabidopsis thaliana flower development. Then, some examples of coupled GRN dynamics in spatiotemporal domains are recalled: cell differentiation in A. thaliana leaf and root epidermis, and the spatiotemporal pattern of genes responsible for the apical shoot meristem behavior. Furthermore, we consider models on auxin transport mechanisms that are sufficient to generate observed morphogenetic shoot and root patterns. We also present several approaches to model signal transduction pathways that consider crosstalk among several biochemical pathways, as well as the influence of environmental factors. In Section 1.5 we consider the constructive role of noise in pattern formation in complex systems. We finally conclude that studies on GRN structure and dynamics aid at understanding evolutionary morphological patterns.

The design of the pad readout electronics of the Warm Iron Calorimeter for the SLD detector at SLAC, consisting of about 9,000 analog channels, is described. Results of various tests performed during the construction, installation and commissioning of the electronics mounted on the detector are presented.

We study the different coherence resonance (CR) phenomena induced when an excitable FitzHugh-Nagumo-type system is forced using diverse deterministic and/or stochastic time series. The possible implications of this comparative study involving these different CR's are also discussed. The main result of the present work suggests that for appropriate forcing and system parameters the generated CR curves reflect the correlations of the superimposed time series.

We report successful manipulation of the noise provoked spiking behavior using delayed feedback control. Experiments were performed in a three electrode electrochemical cell under potentiostatic conditions. The uncontrolled system exhibited noise invoked oscillations whose regularity was quantified using normalized variance (NV). Superimposing delayed feedback, for appropriate values of delay (t), an enhancement in the regularity of the spike sequence was attained. Numerical simulations corroborated experimental observations.

We study the interaction of intrinsic electrochemical noise with autonomous nonlinear dynamics of a three-electrode electrochemical cell. The amplitude of this intrinsic (internal) noise, regulated by the concentration of chloride ions, is monotonically increased and the provoked dynamics is analyzed. The experimentally constructed coherence factor $\ensuremath{\beta}$ versus the concentration of the chloride ions' curve has a unimodal shape indicating the emergence of intrinsic coherence resonance. The abscissa for the maxima of this unimodal curve corresponds to the optimum value of intrinsic noise where maximum regularity of the invoked dynamics is observed.

Aperiodic stochastic resonance in an electrochemical system with excitable dynamics is characterized in experiments and simulations. Two different spike trains, one with stochastic and the other with chaotic interspike intervals, are imposed on the system as subthreshold aperiodic signals. Information transmission is quantified by the cross correlation between the subthreshold input signal and the noise induced system response. A maximum is exhibited in the input-output correlation as a function of the noise amplitude. Numerical simulations with an electrochemical model are in excellent agreement with the experimental observations.

We report evidence of coexisting period stochastic resonance (PSR) and coherence resonance (CR) phenomena in an electrochemical cell. The anodic voltage (V) in the cell is chosen such that the anodic current (I) exhibits excitable fixed point behavior. Subsequently, the anodic voltage is modulated by an external perturbation that is a composite of a subthreshold periodic pulse signal and Gaussian white noise (GWN). As the amplitude of the GWN is increased, the regularity of the invoked dynamics is analyzed using normalized variance curve. The calculated resonance curve shows a double minima, implying the existence of two optimum noise levels where enhanced regularity of the induced spike sequence is detected. Numerical simulations corroborate experimental findings.

The interaction of external noise with an electrochemical oscillator (anodic dissolution of iron) has been studied experimentally on both sides of the homoclinic bifurcation. In the oscillatory regime the regularity of the limit cycle behavior was destroyed with increasing noise amplitude until no periodicity was observable any more. In contrast, the response of the excitable state (fixed point regime) became more regular at intermediate noise levels.

Interaction of noise with nonlinear chemical dynamics is studied experimentally. In particular, noise invoked resonance phenomena are investigated. The existence of the standard Coherence Resonance (CR) and Periodic Stochastic Resonance (PSR) effects, manifested by signature unimodal curves, are verified in experiments. Moreover, the possibility of the coexistence of CR and PSR is entertained. This coexistence is subsequently confirmed by the bimodal shape of the generated resonance curve.

Experimental and numerical evidence of coherence resonance in an electrochemical system is reported. External noise with a Gaussian distribution is superimposed on the system when the anodic current is exhibiting stationary (fixed point) dynamics below a supercritical Hopf bifurcation. The amplitude of the added stochastic perturbations is increased monotonically and the induced oscillatory behavior is analyzed. It is observed, both in experiments and in simulations, that the regularity of the noise induced current oscillations reaches a maximum value for an optimum noise level. This is indicative of coherence resonance and can be explained with a mechanism based on noisy precursors to a Hopf bifurcation.

The elastic differential cross section is calculated at low energies (below 100 MeV) for the elements 3 He, 20 Ne, 40 Ar, 14 N, 12 C, and for the 208 Pb using a finite electromagnetic potential, which is obtained by considering a Randall– Sundrum II scenario modified by the inclusion of p compact extra-dimensions. The length scale is adjusted in the potential to compare with known experimental data and to set bounds for the parameter of the model. The effective four-dimensional (4D) electromagnetic potential is produced by a point charge, as seen from the three-brane that contains it, in uniform motion in an RSIIp scenario.

We study periodic and coherence resonances invoked by aperiodic yet deterministic perturbations. Chaotic perturbations with varying levels of intrinsic correlations are superimposed parametrically on an excitable chemical model. This enables us to analyze the system response and characterize the induced resonances as a function of correlation in the perturbing signal. Using standard measures such as normalized variance and normalized number of peaks, dynamics for different deterministic signals are quantified and eventually compared to resonances invoked via stochastic perturbations.

We introduce a nonlinear dynamical system with self-exciting chaotic dynamics. Its interspike interval return map shows a noisy Poisson-like distribution. Spike sequences from different initial conditions are unrelated but possess the same mean frequency. In the presence of noisy perturbations, sequences started from different initial conditions synchronize. The features of the model are compared with experimental results for irregular spike sequences in neurons. Self-exciting chaos offers a mechanism for temporal coding of complex input signals.

This study investigates the vascularization of the Achilles tendon in 32 lower limbs of human neonates by injecting colored latex with subsequent microdissection. Because of its biomechanical significance (achilleo-calcaneal-plantar system) and the lack of descriptions in the literature, we analyzed the vascularization of the attachment area in the calcaneus, describing the achilleo-calcaneal vascular network, which is always well supplied in contrast to other tendinous areas.

Presentamos nuestra experiencia en roturas de clavos intramedirlares de fémur en el período comprendido entre 1982-1990. Durante el mismo se realizaron 54 extracciones. En un caso se produjo la rotura previamente a la extraccihn, y en dos la rotura fue intraoperatoria. Dicha eventualidad motiva el presente estudio.

We present the first measurement of the left-right cross-section asymmetry (ALR) in Z-boson production observed at the SLAC Linear Collider. In 1992 the SLD detector recorded 10 224 Z events produced by the collision of longitudinally polarized electrons with an unpolarized positron beam at a center-of-mass energy of 91.55 GeV. The average electron beam polarization during the run was (22.4 ± 0.6)%. We measure ALR to be 0.100 ± 0.0440 (stat.) ±0.004 (syst.), which determines the effective weak mixing angle to be $\sin^2\theta_W^{\rm {eff}} = 0.2378\pm 0.0056\, ({\rm stat.})\pm 0.0005\, ({\rm syst.})$.