71 research outputs found

    Comparison of Clinical and Hemodynamic Effects of Isoflurane and Sevoflurane Anesthesia in Calves

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    Background: Inhalation anesthesia is the preferred method for use on many animal species, including ruminants, due to its superiority over the injectable anesthetics. The most commonly used inhalation anesthetics are isoflurane and sevoflurane The aim of the study was to investigate the effects of isoflurane and sevoflurane anesthesia on the cardiovascular system of calves.Materials, Methods & Results: A total of 20 calves (11 male, 9 female) between 1 and 6 months in age and 50 to 85 kg in body weight were used. The calves were divided randomly into two groups of 10 each, with one group being administered isoflurane and the other sevoflurane. An intramuscular dosage of 0.1 mg/kg of xylazine was administered to the calves as premedication. Induction was performed 10 min after calves were given an intramuscular dosage of 4 mg/kg of ketamine. Inhalation anesthesia was maintained with isoflurane or sevoflurane in 100% oxygen saturation. Before anesthesia, after induction and at intervals of 5, 10, 15, 20, 25, 30, 45, and 60 min of anesthesia, the body temperature, heart rate, and respiratory rate of the calves were recorded. Additionally, before anesthesia, after induction and at intervals of 15, 30, 45, and 60 min of anesthesia, serum electrolyte (Na+, Ca++, K+, Mg++) and blood gases (pH, pCO2, pO2, HCO3-, TCO2, O2Sat, HCT) were evaluated from blood samples taken from both groups. The second derivation, durations and amplitudes of the P and T waves, the durations and amplitudes of the QRS complex, and the durations of PQ and QT intervals were evaluated on the ECGs recorded before anesthesia, after induction and during anesthesia. Following anesthesia termination, the extubation time and the time it took for straightening of the head and standing up were recorded. Decrease in heart rate and body temperature were found significant in two of the groups. Decrease in respiratory rate compared to initial values after premedication was statistically significant for both groups. However, during anesthesia, an increase occurred. This incresae in respiration rate was not statistically significant compared to initial values. The incease in the values of pCO2, pO2, HCO3 and the decrease in the values of pH and Hct comparing the initial values was found statistically significant in both groups.Discussion: In ruminants, isoflurane has an induction concentration of 3-5% and an anesthetic concentration of 1.5-3%, while sevoflurane has an induction concentration of 4-6% and an anesthetic concentration of 2.5-4%. In this study, the concentration of isoflurane was 2.3% (2-5) and the of sevoflurane was 4.07% (3-5) for surgery. In the isoflurane group, extubation, straightening of the head and standing up times were 12.40 ± 3.77 min, 20.4 ± 1.57 min, and 30.80 ± 1.89 min, respectively. In the sevoflurane group, extubation, straightening of the head and standing up times were 13.40 ± 4.99, 19.2 ± 1.49, and 28.0 ± 1.83 min, respectively. Although the calves in the isoflurane group were extubated earlier than those of the sevoflurane group, the time elapsed for straightening of the head and standing up were longer than that of the sevoflurane group. The anesthesia protocol provided a smooth anesthetic administration, general anesthesia and awakening. In conclusion, the effects of isoflurane and sevoflurane anesthesia on the cardiovascular and respiratory system were similar, and although the changes that emerged during anesthesia were statistically significant, it was nonetheless found that the changes were within the physiological limits

    Alpha head on collision with a fixed gold nucleus, taking into account the relativistic rest mass variation as implied by mass-energy equivalence

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    We reformulate the Rutherford scattering of alpha particle for a head on collision, taking into account the rest mass variation of the particle, as implied by the energy conservation law. Our relativistic reformulation (which includes the energy conservation) constitutes a new example for the breakdown of the Lorentz invariance. Briefly speaking, even at rest or during the whole scattering process, the distance between the alpha particle and the gold nucleus is not invariant but depends on the frame of the observer attached to either object. According to our relativistic reformulation, we also provide a new set of Lorentz transformations.Publisher's Versio

    Experience of isavuconazole as a salvage therapy in chronic pulmonary fungal disease

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    Background: Instances of resistant fungal infection are rising in pulmonary disease, with limited therapeutic options. Therapeutic drug monitoring of azole antifungals has been necessary to ensure safety and efficacy but is considered unnecessary for the newest triazole isavuconazole. Aims: To characterise the prevalence of isavuconazole resistance and use in a tertiary respiratory centre. Methods: A retrospective observational analysis (2016–2021) of adult respiratory patients analysing fungal culture, therapeutic drug monitoring, and outcome post-isavuconazole therapy. Results: During the study period, isavuconazole susceptibility testing was performed on 26 Aspergillus spp. isolates. A total of 80.8% of A. fumigatus isolates had isavuconazole (MIC > 1 mg/L, and 73.0% > 2 mg/L) with a good correlation to voriconazole MIC (r = 0.7, p = 0.0002). A total of 54 patients underwent isavuconazole therapy during the study period (median duration 234 days (IQR: 24–499)). A total of 67% of patients tolerated isavuconazole, despite prior azole toxicity in 61.8%, with increased age (rpb = 0.31; p = 0.021) and male sex (φc = 0.30; p = 0.027) being associated with toxicity. A total of 132 isavuconazole levels were performed with 94.8% > 1 mg/L and 72% > 2 mg/L. Dose change from manufacturer’s recommendation was, however, required in 9.3% to achieve a concentration of >2 mg/L. Conclusion: We describe the use of isavuconazole as a salvage therapy in a chronic pulmonary fungal disease setting with a high prevalence of azole resistance. Therapeutic concentrations at standard dosing were high; however, results reinforce antifungal stewardship for optimization

    Patients with Black Hip and Black Knee Due to Ochronotic Arthropathy: Case Report and Review of Literature

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    Abstract Ochronotic arthropathy is a manifestation of longstanding alkaptonuria. With increasing age, an accumulation of pigment deposits of homogentisic acid in the joint cartilage results in ochronotic osteoarthritis. We present a case of a 62-year-old female who underwent staged left uncemented total hip and right cemented total knee arthroplasty for osteoarthritis secondary to ochronosis

    Patients with Black Hip and Black Knee Due to Ochronotic Arthropathy: Case Report and Review of Literature

    Get PDF
    Ochronotic arthropathy is a manifestation of longstanding alkaptonuria. With increasing age, an accumulation of pigment deposits of homogentisic acid in the joint cartilage results in ochronotic osteoarthritis. We present a case of a 62-year-old female who underwent staged left uncemented total hip and right cemented total knee arthroplasty for osteoarthritis secondary to ochronosis

    Continuous-time quantum walks for MAX-CUT are hot

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    By exploiting the link between time-independent Hamiltonians and thermalisation, heuristic predictions on the performance of continuous-time quantum walks for MAX-CUT are made. The resulting predictions depend on the number of triangles in the underlying MAX-CUT graph. We extend these results to the time-dependent setting with multi-stage quantum walks and Floquet systems. The approach followed here provides a novel way of understanding the role of unitary dynamics in tackling combinatorial optimisation problems with continuous-time quantum algorithms.Comment: 25 pages, 29 figure

    Observation of the nonlinear Hall effect under time reversal symmetric conditions

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    The electrical Hall effect is the production of a transverse voltage under an out-of-plane magnetic field. Historically, studies of the Hall effect have led to major breakthroughs including the discoveries of Berry curvature and the topological Chern invariants. In magnets, the internal magnetization allows Hall conductivity in the absence of external magnetic field. This anomalous Hall effect (AHE) has become an important tool to study quantum magnets. In nonmagnetic materials without external magnetic fields, the electrical Hall effect is rarely explored because of the constraint by time-reversal symmetry. However, strictly speaking, only the Hall effect in the linear response regime, i.e., the Hall voltage linearly proportional to the external electric field, identically vanishes due to time-reversal symmetry. The Hall effect in the nonlinear response regime, on the other hand, may not be subject to such symmetry constraints. Here, we report the observation of the nonlinear Hall effect (NLHE) in the electrical transport of the nonmagnetic 2D quantum material, bilayer WTe2. Specifically, flowing an electrical current in bilayer WTe2 leads to a nonlinear Hall voltage in the absence of magnetic field. The NLHE exhibits unusual properties sharply distinct from the AHE in metals: The NLHE shows a quadratic I-V characteristic; It strongly dominates the nonlinear longitudinal response, leading to a Hall angle of about 90 degree. We further show that the NLHE directly measures the "dipole moment" of the Berry curvature, which arises from layer-polarized Dirac fermions in bilayer WTe2. Our results demonstrate a new Hall effect and provide a powerful methodology to detect Berry curvature in a wide range of nonmagnetic quantum materials in an energy-resolved way
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