Chronic Obstructive Pulmonary Disease in Heart Failure: Challenges in Diagnosis and Treatment for HFpEF and HFrEF.

PURPOSE OF REVIEW: Chronic obstructive pulmonary disease (COPD) is common in heart failure (HF), and it has a significant impact on the prognosis and quality of life of patients. Additionally, COPD is independently associated with lower adherence to first-line HF therapies. In this review, we outline the challenges of identifying and managing HF with preserved (HFpEF) and reduced (HFrEF) ejection fraction with coexisting COPD. RECENT FINDINGS: Spirometry is necessary for COPD diagnosis and prognosis but is underused in HF. Therefore, misdiagnosis is a concern. Also, disease-modifying drugs for HF and COPD are usually safe but underprescribed when HF and COPD coexist. Patients with HF-COPD are poorly enrolled in clinical trials. Guidelines recommend that HF treatment should be offered regardless of COPD presence, but modern registries show that undertreatment persists. Treatment gaps could be attenuated by ensuring an accurate and earlier COPD diagnosis in patients with HF, clarifying the concerns related to pharmacotherapy safety, and increasing the use of non-pharmacologic treatments. Acknowledging the uncertainties, this review aims to provide key clinical resources to support better physician-patient co-decision-making and improve collaboration between health professionals.

Thoracoabdominal asynchrony associates with exercise intolerance in fibrotic interstitial lung diseases.

BACKGROUND AND OBJECTIVE: The precise coordination of respiratory muscles during exercise minimizes work of breathing and avoids exercise intolerance. Fibrotic interstitial lung disease (f-ILD) patients are exercise-intolerant. We assessed whether respiratory muscle incoordination and thoracoabdominal asynchrony (TAA) occur in f-ILD during exercise, and their relationship with pulmonary function and exercise performance. METHODS: We compared breathing pattern, respiratory mechanics, TAA and respiratory muscle recruitment in 31 f-ILD patients and 31 healthy subjects at rest and during incremental cycle exercise. TAA was defined as phase angle (PhAng) >20°. RESULTS: During exercise, when compared with controls, f-ILD patients presented increased and early recruitment of inspiratory rib cage muscle (p < 0.05), and an increase in PhAng, indicating TAA. TAA was more frequent in f-ILD patients than in controls, both at 50% of the maximum workload (42.3% vs. 10.7%, p = 0.01) and at the peak (53.8% vs. 23%, p = 0.02). Compared with f-ILD patients without TAA, f-ILD patients with TAA had lower lung volumes (forced vital capacity, p < 0.01), greater dyspnoea (Medical Research Council > 2 in 64.3%, p = 0.02), worse exercise performance (lower maximal work rate % predicted, p = 0.03; lower tidal volume, p = 0.03; greater desaturation and dyspnoea, p < 0.01) and presented higher oesophageal inspiratory pressures with lower gastric inspiratory pressures and higher recruitment of scalene (p < 0.05). CONCLUSION: Exercise induces TAA and higher recruitment of inspiratory accessory muscle in ILD patients. TAA during exercise occurred in more severely restricted ILD patients and was associated with exertional dyspnoea, desaturation and limited exercise performance.

ERS statement on respiratory muscle testing at rest and during exercise.

Assessing respiratory mechanics and muscle function is critical for both clinical practice and research purposes. Several methodological developments over the past two decades have enhanced our understanding of respiratory muscle function and responses to interventions across the spectrum of health and disease. They are especially useful in diagnosing, phenotyping and assessing treatment efficacy in patients with respiratory symptoms and neuromuscular diseases. Considerable research has been undertaken over the past 17 years, since the publication of the previous American Thoracic Society (ATS)/European Respiratory Society (ERS) statement on respiratory muscle testing in 2002. Key advances have been made in the field of mechanics of breathing, respiratory muscle neurophysiology (electromyography, electroencephalography and transcranial magnetic stimulation) and on respiratory muscle imaging (ultrasound, optoelectronic plethysmography and structured light plethysmography). Accordingly, this ERS task force reviewed the field of respiratory muscle testing in health and disease, with particular reference to data obtained since the previous ATS/ERS statement. It summarises the most recent scientific and methodological developments regarding respiratory mechanics and respiratory muscle assessment by addressing the validity, precision, reproducibility, prognostic value and responsiveness to interventions of various methods. A particular emphasis is placed on assessment during exercise, which is a useful condition to stress the respiratory system.

Diaphragmatic ultrasound findings correlate with dyspnea, exercise tolerance, health-related quality of life and lung function in patients with fibrotic interstitial lung disease.

BACKGROUND: Fibrotic interstitial lung disease (FILD) patients are typically dyspneic and exercise-intolerant with consequent impairment of health-related quality of life (HRQoL). Respiratory muscle dysfunction is among the underlying mechanisms of dyspnea and exercise intolerance in FILD but may be difficult to diagnose. Using ultrasound, we compared diaphragmatic mobility and thickening in FILD cases and healthy controls and correlated these findings with dyspnea, exercise tolerance, HRQoL and lung function. METHODS: We measured diaphragmatic mobility and thickness during quiet (QB) and deep breathing (DB) and calculated thickening fraction (TF) in 30 FILD cases and 30 healthy controls. We correlated FILD cases' diaphragmatic findings with dyspnea, exercise tolerance (six-minute walk test), lung function and HRQoL (St. George's Respiratory Questionnaire). RESULTS: Diaphragmatic mobility was similar between groups during QB but was lower in FILD cases during DB when compared to healthy controls (3.99 cm vs 7.02 cm; p <  0.01). FILD cases showed higher diaphragm thickness during QB but TF was lower in FILD when compared to healthy controls (70% vs 188%, p <  0.01). During DB, diaphragmatic mobility and thickness correlated with lung function, exercise tolerance and HRQoL, but inversely correlated with dyspnea. Most FILD cases (70%) presented reduced TF, and these patients had higher dyspnea and exercise desaturation, lower HRQoL and lung function. CONCLUSION: Compared to healthy controls, FILD cases present with lower diaphragmatic mobility and thickening during DB that correlate to increased dyspnea, decreased exercise tolerance, worse HRQoL and worse lung function. FILD cases with reduced diaphragmatic thickening are more dyspneic and exercise-intolerant, have lower HRQoL and lung function.

Accuracy of Invasive and Noninvasive Parameters for Diagnosing Ventilatory Overassistance During Pressure Support Ventilation.

OBJECTIVE: Evaluate the accuracy of criteria for diagnosing pressure overassistance during pressure support ventilation. DESIGN: Prospective clinical study. SETTING: Medical-surgical ICU. PATIENTS: Adults under mechanical ventilation for 48 hours or more using pressure support ventilation and without any sedative for 6 hours or more. Overassistance was defined as the occurrence of work of breathing less than 0.3 J/L or 10% or more of ineffective inspiratory effort. Two alternative overassistance definitions were based on the occurrence of inspiratory esophageal pressure-time product of less than 50 cm H2O s/min or esophageal occlusion pressure of less than 1.5 cm H2O. INTERVENTIONS: The pressure support was set to 20 cm H2O and decreased in 3-cm H2O steps down to 2 cm H2O. MEASUREMENTS AND MAIN RESULTS: The following parameters were evaluated to diagnose overassistance: respiratory rate, tidal volume, minute ventilation, peripheral arterial oxygen saturation, rapid shallow breathing index, heart rate, mean arterial pressure, change in esophageal pressure during inspiration, and esophageal and airway occlusion pressure. In all definitions, the respiratory rate had the greatest accuracy for diagnosing overassistance (receiver operating characteristic area = 0.92; 0.91 and 0.76 for work of breathing, pressure-time product and esophageal occlusion pressure in definition, respectively) and always with a cutoff of 17 incursions per minute. In all definitions, a respiratory rate of less than or equal to 12 confirmed overassistance (100% specificity), whereas a respiratory rate of greater than or equal to 30 excluded overassistance (100% sensitivity). CONCLUSION: A respiratory rate of 17 breaths/min is the parameter with the greatest accuracy for diagnosing overassistance. Respiratory rates of less than or equal to 12 or greater than or equal to 30 are useful clinical references to confirm or exclude pressure support overassistance.

Dimensioning of a multibeam coherent photonic beamformer fed by a phased array antenna.

The design and dimensioning of a photonic-aided payload for a multi-beam high-throughput communications satellite is a complex problem in which the antenna, RF and photonic subsystems must be considered as a whole for achieving best performance with lowest mass and power consumption. In this paper, we propose and dimension the receiving stage of a communications satellite comprising a phased array antenna (PAA) feeding a multibeam photonic beamforming system (PBS). The PBS uses a single wavelength and resorts to heterodyne detection such that the retrieved beams are frequency downconverted. End-to-end system modeling shows that the complexity of the PAA and PBS can be traded-off for signal-to-noise ratio (SNR) or power consumption without compromising the beam width. The dimensioning of a realistic scenario is presented, showing that an SNR and beam crosstalk on the order of 20 dB are achievable with a total power consumption below 1 kW for a typical number of 100 antenna elements (AEs).

Unilateral diaphragm paralysis: a dysfunction restricted not just to one hemidiaphragm.

BACKGROUND: Most patients with unilateral diaphragm paralysis (UDP) have unexplained dyspnea, exercise limitations, and reduction in inspiratory muscle capacity. We aimed to evaluate the generation of pressure in each hemidiaphragm separately and its contribution to overall inspiratory strength. METHODS: Twenty-seven patients, 9 in right paralysis group (RP) and 18 in left paralysis group (LP), with forced vital capacity (FVC) < 80% pred, and 20 healthy controls (CG), with forced expiratory volume in 1 s (FEV1) > 80% pred and FVC > 80% pred, were evaluated for lung function, maximal inspiratory (MIP) and expiratory (MEP) pressure measurements, diaphragm ultrasound, and transdiaphragmatic pressure during magnetic phrenic nerve stimulation (PdiTw). RESULTS: RP and LP had significant inspiratory muscle weakness compared to controls, detected by MIP (- 57.4 ± 16.9 for RP; - 67.1 ± 28.5 for LP and - 103.1 ± 30.4 cmH2O for CG) and also by PdiTW (5.7 ± 4 for RP; 4.8 ± 2.3 for LP and 15.3 ± 5.7 cmH2O for CG). The PdiTw was reduced even when the non-paralyzed hemidiaphragm was stimulated, mainly due to the low contribution of gastric pressure (around 30%), regardless of whether the paralysis was in the right or left hemidiaphragm. On the other hand, in CG, esophagic and gastric pressures had similar contribution to the overall Pdi (around 50%). Comparing both paralyzed and non-paralyzed hemidiaphragms, the mobility during quiet and deep breathing, and thickness at functional residual capacity (FRC) and total lung capacity (TLC), were significantly reduced in paralyzed hemidiaphragm. In addition, thickness fraction was extremely diminished when contrasted with the non-paralyzed hemidiaphragm. CONCLUSIONS: In symptomatic patients with UDP, global inspiratory strength is reduced not only due to weakness in the paralyzed hemidiaphragm but also to impairment in the pressure generated by the non-paralyzed hemidiaphragm.

Pulmonary rehabilitation in lymphangioleiomyomatosis: a controlled clinical trial.

Lymphangioleiomyomatosis (LAM) is a cystic lung disease frequently associated with reduced exercise capacity. The aim of this study was to assess safety and efficacy of pulmonary rehabilitation in LAM.This controlled clinical trial included 40 patients with LAM and a low physical activity level. The pulmonary rehabilitation programme comprised 24 aerobic and muscle strength training sessions and education. The primary outcome was exercise capacity (endurance time during a constant work rate exercise test). Secondary outcomes included health-related quality of life (St George's Respiratory Questionnaire (SGRQ)), 6-min walking distance (6MWD), dyspnoea, peak oxygen consumption (V'O2 ), daily physical activity (pedometer), symptoms of anxiety and depression, lung function and peripheral muscle strength (one-repetition maximum).The baseline characteristics were well balanced between the groups. The pulmonary rehabilitation group exhibited improvements in the following outcomes versus controls: endurance time (median (interquartile range) 169 (2-303) s versus -33 (-129-39) s; p=0.001), SGRQ (median (interquartile range) -8 (-16-2) versus 2 (-4-5); p=0.002) and 6MWD (median (interquartile range) 59 (13-81) m versus 20 (-12-30) m; p=0.002). Dyspnoea, peak V'O2 , daily physical activity and muscle strength also improved significantly. No serious adverse events were observed.Pulmonary rehabilitation is a safe intervention and improves exercise capacity, dyspnoea, daily physical activity, quality of life and muscle strength in LAM.

Pump-phase-noise-free optical wavelength data exchange between QAM signals with 50-GHz channel-spacing using coherent DFB pump.

An important challenge for implementing optical signal processing functions such as wavelength conversion or wavelength data exchange (WDE) is to avoid the introduction of linear and nonlinear phase noise in the subsystem. This is particularly important for phase noise sensitive, high-order quadrature-amplitude modulation (QAM) signals. In this paper, we propose and experimentally demonstrate an optical data exchange scheme through cascaded 2nd-order nonlinearities in periodically-poled lithium niobate (PPLN) waveguides using coherent pumping. The proposed coherent pumping scheme enables noise from the coherent pumps to be cancelled out in the swapped data after WDE, even with broad linewidth distributed feedback (DFB) pump lasers. Hence, this scheme allows phase noise tolerant processing functions, enabling the low-cost implementation of WDE for high-order QAM signals. We experimentally demonstrate WDEs between 10-Gbaud 4QAM (4QAM) signal and 12.5-Gbaud 4QAM (16QAM) signal with 3.5-MHz linewidth DFB pump lasers and 50-GHz channel spacing. Error-free operation is observed for the swapped QAM signals with coherent DFB pumping whilst use of free-running DFB pumps leads to visible error floors and unrecoverable phase errors. The phase noise cancellation in the coherent pump scheme is further confirmed by study of the recovered carrier phase of the converted signals. In addition to pump phase noise, the influence of crosstalk caused by the finite extinction ratio in WDE is also experimentally investigated for the swapped QAM signals.

Experimental investigation of phase-sensitive amplification of data signals in a four-mode fiber-based PSA.

In this Letter, we investigate the influence of the phase and power of pump and signal waves on the gain of a four-mode phase-sensitive amplifier (PSA) built with a highly nonlinear fiber (HNLF), using a copier + PSA scheme to generate phase- and frequency-correlated idler waves. Using such an amplifier, low-noise amplification of a 10 Gsymbol/s quadrature phase-shift keying (QPSK) signal, with net gain of ∼20 dB and less than 1 dB optical signal-to-noise ratio (OSNR) penalty at a bit error ratio (BER) of 10(-3), was achieved. We also verified an additional net gain of 11.6 dB when switching from phase-insensitive to phase-sensitive operation, which is in good agreement with theoretical predictions of 12 dB.

Pump-linewidth-tolerant optical wavelength conversion for high-order QAM signals using coherent pumps.

Optical wavelength conversion (OWC) is expected to be a desirable function in future optical transparent networks. Since high-order quadrature amplitude modulation (QAM) is more sensitive to the phase noise, in the OWC of high-order QAM signals, it is crucial to suppress the extra noise introduced in the OWC subsystem, especially for the scenario with multiple cascaded OWCs. Here, we propose and experimentally demonstrate a pump-linewidth-tolerant OWC scheme suitable for high-order QAM signals using coherent two-tone pumps. Using 3.5-MHz-linewidth distributed feedback (DFB) lasers as pump sources, our scheme enables wavelength conversion of both 16QAM and 64QAM signals with negligible power penalty, in a periodically-poled Lithium Niobate (PPLN) waveguide based OWC. We also demonstrate the performance of pump phase noise cancellation, showing that such coherent two-tone pump schemes can eliminate the need for ultra-narrow linewidth pump lasers and enable practical implementation of low-cost OWC in future dynamic optical networks.

Differences of ventilatory muscle recruitment and work of breathing in COPD and interstitial lung disease during exercise: a comprehensive evaluation.

Introduction: COPD and interstitial lung disease (ILD) are significant chronic respiratory disorders, impacting quality of life. Respiratory muscle roles and differences remain not entirely clear. The objective of the present study was to evaluate the degree of recruitment of the respiratory muscles and the work of breathing in COPD and ILD during exercise. Methods: We compared the sensory-mechanical relationships in COPD, ILD and healthy controls (n=20 each). They performed pulmonary function, noninvasive and invasive respiratory muscle strength, surface electromyography and work-of-breathing assessments. Results: COPD and ILD did not show lower static muscle strength compared to controls, but did show poor performance in the exercise test with increased transdiaphragmatic pressure (P di). In ILD, there was a higher increase in oesophageal pressure and a lower gastric pressure (P ga) on inspiration; in COPD, there was a significant increase in P ga on inspiration. In ILD, there is greater recruitment of accessory inspiratory muscles, whereas in COPD, there is marked use of both inspiratory and expiratory muscles. The neuromechanical inefficiency (increased neural respiratory drive without the corresponding tidal volume) was found in both diseases. In COPD, there is a considerable increase in elastic work to overcome intrinsic positive end-expiratory pressure (PEEPi) and expiratory work of breathing, whereas in ILD, non-PEEPi elastic work of breathing is the highest part of the total work of breathing. Conclusions: Early and increased activity of the respiratory muscles and work-of-breathing components significantly contribute to dyspnoea, exercise intolerance and neuromechanical inefficiency of ventilation in COPD and ILD. The mechanisms of P di generation were different between diseases.

Phase-sensitive amplification in a single bi-directional PPLN waveguide.

We investigate phase-sensitive amplification (PSA) and phase regeneration of a binary phase-shift keying (BPSK) signal using a single periodically poled lithium niobate (PPLN) waveguide. The PPLN is operated bi-directionally in order to simultaneously achieve phase correlated signals and phase-sensitive (PS) operation. We use injection-locking for carrier phase recovery and a lead zirconate titanate (PZT) fiber stretcher to correct path length deviations in the in-line phase regenerator. We observe a trade-off between high PS gain provided by high pumping power and stability of the device.

Exercise performance and dynamic hyperinflation in lymphangioleiomyomatosis.

RATIONALE: Lymphangioleiomyomatosis (LAM) is characterized by exercise performance impairment. Although airflow limitation is common, no previous studies have evaluated the prevalence and impact of dynamic hyperinflation (DH) in LAM. OBJECTIVES: To investigate the dynamic responses during maximal exercise and the prevalence, predictors, and repercussions of DH in LAM. METHODS: Forty-two patients with LAM performed symptom-limited incremental cycle exercise and pulmonary functions tests (PFTs) and were compared with 10 age-matched healthy women. Dyspnea intensity, inspiratory capacity, oxygen saturation, and cardiac, metabolic, and respiratory variables were assessed during exercise. Patients with LAM also performed a 6-minute walk test (6MWT). MEASUREMENTS AND MAIN RESULTS: Patients with LAM had higher baseline dyspnea, poorer quality of life, obstructive pattern, air trapping, and reduced diffusing capacity of carbon monoxide in PFTs. Although they had the same level of regular physical activity, their maximal exercise performance was reduced and was associated with ventilatory limitation, greater desaturation, and dyspnea. The prevalence of DH was high in LAM (55%), even in patients with mild spirometric abnormalities, and was correlated with airflow obstruction, air trapping, and diffusing capacity of carbon monoxide. Compared with the non-DH subgroup, the patients who developed DH had a ventilatory limitation contributing to exercise cessation on cycling and higher desaturation and dyspnea intensity during the 6MWT. CONCLUSIONS: Ventilatory limitation and gas exchange impairment are important causes of exercise limitation in LAM. DH is frequent in LAM, even in patients with mild spirometric abnormalities. DH was associated with the severity of disease, higher dyspnea, and lower oxygen saturation. In the 6MWT, desaturation and dyspnea were greater in patients with DH.

Diaphragm Ultrasound in Critically Ill Patients on Mechanical Ventilation-Evolving Concepts.

Mechanical ventilation (MV) is a life-saving respiratory support therapy, but MV can lead to diaphragm muscle injury (myotrauma) and induce diaphragmatic dysfunction (DD). DD is relevant because it is highly prevalent and associated with significant adverse outcomes, including prolonged ventilation, weaning failures, and mortality. The main mechanisms involved in the occurrence of myotrauma are associated with inadequate MV support in adapting to the patient's respiratory effort (over- and under-assistance) and as a result of patient-ventilator asynchrony (PVA). The recognition of these mechanisms associated with myotrauma forced the development of myotrauma prevention strategies (MV with diaphragm protection), mainly based on titration of appropriate levels of inspiratory effort (to avoid over- and under-assistance) and to avoid PVA. Protecting the diaphragm during MV therefore requires the use of tools to monitor diaphragmatic effort and detect PVA. Diaphragm ultrasound is a non-invasive technique that can be used to monitor diaphragm function, to assess PVA, and potentially help to define diaphragmatic effort with protective ventilation. This review aims to provide clinicians with an overview of the relevance of DD and the main mechanisms underlying myotrauma, as well as the most current strategies aimed at minimizing the occurrence of myotrauma with special emphasis on the role of ultrasound in monitoring diaphragm function.

Vocal Impact in Patients With Unilateral Diaphragmatic Paralysis.

OBJECTIVES: This study aimed to investigate the possible vocal impact confirmed by diagnostic tests, the degree of perception of possible vocal impairment by patients with Unilateral Diaphragmatic paralysis (UDP) and its correlation with ventilatory weakness. METHODS: The researchers conducted an analytical, observational and case-control study with 70 individuals, including 35 UDP patients and 35 healthy patients in a control group, who underwent the following assessments: 1) Self-assessment of voice handicap (VHI-10); 2) Self-Assessment of Quality of Life (SF-36); 3) Self-Assessment of Dyspnea (MRC); 4) Objective vocal measures (Maximum Phonation Time (MPT) in /a/, /s/, /z/ and glottal-to-noise excitation ratio); 5) Functional respiratory pressures (Spirometry and maximum ventilatory pressures); 6) General degree of dysphonia - G on the GRBAS Scale. The sex, age and body mass index (BMI) of the individuals were the variables used to match the sample of this study. RESULTS: When compared with controls, patients with UDP had a restrictive functional pattern and inspiratory weakness, with symptoms of dyspnea and worsening quality of life. When associated with a possible vocal impact, these patients had voice handicap and decreased MPT values for all phonemes, especially /a/. There was also a correlation between vocal performance and inspiratory weakness. However, it should be noted that, despite having vocal impairment, many patients did not report the perception of this fact, somehow neglecting such impairment. CONCLUSIONS: In addition to the expected weakness of the ventilatory muscles, patients with UDP had clinically verified vocal impact, and those who had greater inspiratory weakness also had greater voice impairment. Finally, it is relevant that not all patients perceived such vocal impact, which showed a very reduced perception of this impairment in patients with UDP.

A TaqMan® Assay Allows an Accurate Detection and Quantification of Fusarium spp., the Causal Agents of Tomato Wilt and Rot Diseases.

In tomato plants, Fusarium spp. have been increasingly associated with several wilt and rot diseases that are responsible for severe yield losses. Here, we present a real-time PCR TaqMan® MGB (Minor Groove Binder) assay to detect and discriminate Fusarium spp. from other fungal species that affect tomato plants. The methodology used is based on the selective amplification of the internal transcribed spacer (ITS) region of Fusarium spp. This assay revealed to be highly specific and sensitive for Fusarium species, targeting only the 29 Fusarium isolates from the 45 tested isolates associated to tomato diseases. Sensitivity was assessed with serial dilutions of Fusarium genomic DNA, with the limit of detection of 3.05 pg. An absolute DNA quantification method was also established, based on the determination of the absolute number of target copies. Finally, the effectiveness of the assay was successfully validated with the detection and quantification of Fusarium spp. in potentially infected tomato plants from an experimental field and in control plants grown under controlled conditions. The established methodology allows a reliable, sensitive, and reproducible estimation of Fusarium accumulation in infected tomato plants, gaining new insights for disease control and providing an additional tool in the screening of resistant plants.

Outdoor Finishing of Intact Male Portuguese Alentejano Pigs on a Sustainable High-Fiber Diet: Impacts on Blood, Growth, Carcass, Meat Quality and Boar Taint Compounds.

This trial evaluated the effect of sex on the blood, growth, carcass, meat quality, and boar taint compounds in male Alentejano (AL) pigs (n = 30). From ~40 to 130 kg LW, castrated (C) and intact pigs (I and IExp groups) were fed commercial diets ad libitum. Between ~130 and 160 kg (slaughter), C and I pigs continued on commercial diets, while IExp were fed an experimental diet containing locally produced pulses and by-products aimed at reducing boar taint. At ~160 kg, blood urea levels were higher in IExp than C pigs, triacylglycerols were lower in both intact groups, and cortisol was lower in IExp. IExp pigs exhibited faster growth, improved feed conversion ratio, carcass higher commercial yield and leaner meat than C pigs. The loin intramuscular fat in intact pigs was lower, less saturated and more polyunsaturated, while total collagen was higher. Fat androstenone content was higher in intact pigs and skatole content was similar across treatments, although they were below threshold values for consumer detection. Finally, although boar taint compounds were low in intact AL pigs raised outdoors, adding pulses and by-products to the experimental diet did not result in a reduction in fat skatole content compared to pigs fed the commercial diet.

Evaluation of quality of online shopping services in times of COVID-19 based on E-S-QUAL model and Fuzzy TOPSIS method.

This paper aims to propose an approach to evaluate the quality of online shopping services in times of pandemic COVID-19, from the ordering of quality attributes taking into account customers' perception. The proposed approach was developed from a structured questionnaire containing 25 quality attributes adapted from the E-S-QUAL model and applied to consumers of online shopping services. Fuzzy set theory was used in the approach to simplify the subjectivity of human judgment, along with the extension of Technique for Order Performance by Similarity to Ideal Solution (TOPSIS). Therefore, this research was classified as applied, exploratory, quantitative and survey. To achieve the research objective, 819 questionnaires were collected. Among the main findings, it is highlighted that the attributes "product availability", "products with excellent quality", "confidence in online shopping processes" and "ease of buying online" were the ones that presented the best perceptions of quality by the respondents. At the other end, the attributes "opinion sharing on social networks", "buying online is a good option when you have little time", "distraction in online shopping searches" and "shopping online is a pleasure" showed the highest level of dissatisfaction with the service. Thus, this article highlights the importance of online shopping services in times of the pandemic caused by COVID-19, and its main contribution and originality is the development of an approach that aims to support the decision-making process, establishing strategic actions for the continuous improvement of online shopping services with the reduction of subjectivity in customer perception and with successive refinements.