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INTRODUCTION: The impact of peripheral cytokine levels on the prognosis and treatment of immune checkpoint inhibitor (ICI) myocarditis has not been well studied. OBJECTIVES: This study aimed to identify cytokines that can prognosticate and direct the treatment of ICI myocarditis. METHODS: This was a single-center, retrospective cohort study of patients with ICI myocarditis who had available peripheral cytokine levels between January 2011 and May 2022. Major adverse cardiovascular events (MACEs) were defined as a composite of heart failure with/without cardiogenic shock, arterial thrombosis, life-threatening arrhythmias, pulmonary embolism, and sudden cardiac death. RESULTS: In total, 65 patients with ICI myocarditis had cytokine data available. Patients were mostly males (70%), with a mean age of 67.8 ± 12.7 years. Interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) were the most common cytokines to be elevated with 48/65 (74%) of patients having a peak IL-6 above normal limits (>5 pg/mL) and 44/65 (68%) of patients with peak TNF-α above normal limits (>22 pg/mL). Patients with elevated peak IL-6 had similar 90-day mortality and MACE outcomes compared to those without (10.4% vs. 11.8%, p = 0.878 and 8.8% vs. 17.7%, p = 0.366, respectively). Similarly, those with elevated peak TNF-α had similar 90-day mortality and MACEs compared to those without (29.6% vs. 14.3%, p = 0.182 and 13.6% vs. 4.8%, p = 0.413, respectively). Kaplan-Meier survival analysis also showed that there was not a significant difference between MACE-free survival when comparing elevated and normal IL-6 and TNF-α levels (p = 0.182 and p = 0.118, respectively). MACEs and overall survival outcomes were similar between those who received infliximab and those who did not among all patients and those with elevated TNF-α (p-value 0.70 and 0.83, respectively). CONCLUSION: Peripheral blood levels of IL-6 and TNF-α are the most commonly elevated cytokines in patients with ICI myocarditis. However, their role in the prognostication and guidance of immunomodulatory treatment is currently limited.
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INTRODUCTION: We conducted the first comprehensive evaluation of the therapeutic value and safety profile of transcatheter mitral edge-to-edge repair (TEER) and transcatheter mitral valve replacement (TMVR) in individuals concurrently afflicted with cancer. METHODS: Utilizing the National Inpatient Sample (NIS) dataset, we analyzed all adult hospitalizations between 2016 and 2020 (n = 148,755,036). The inclusion criteria for this retrospectively analyzed prospective cohort study were all adult hospitalizations (age 18 years and older). Regression and machine learning analyses in addition to model optimization were conducted using ML-PSr (Machine Learning-augmented Propensity Score adjusted multivariable regression) and BAyesian Machine learning-augmented Propensity Score (BAM-PS) multivariable regression. RESULTS: Of all adult hospitalizations, there were 5790 (0.004%) TMVRs and 1705 (0.001%) TEERs. Of the total TMVRs, 160 (2.76%) were done in active cancer. Of the total TEERs, 30 (1.76%) were done in active cancer. After the comparable rates of TEER/TMVR in active cancer in 2016, the prevalence of TEER/TMVR was significantly less in active cancer from 2017 to 2020 (2.61% versus 7.28% p < 0.001). From 2017 to 2020, active cancer significantly decreased the odds of receiving TEER or TMVR (OR 0.28, 95%CI 0.13-0.68, p = 0.008). In patients with active cancer who underwent TMVR/TEER, there were no significant differences in socio-economic disparities, mortality or total hospitalization costs. CONCLUSION: The presence of malignancy does not contribute to increased mortality, length of stay or procedural costs in TMVR or TEER. Whereas the prevalence of TMVR has increased in patients with active cancer, the utilization of TEER in the context of active cancer is declining despite a growing patient population.
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Inteligencia Artificial , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Neoplasias , Puntaje de Propensión , Humanos , Masculino , Femenino , Neoplasias/cirugía , Neoplasias/economía , Neoplasias/mortalidad , Neoplasias/epidemiología , Anciano , Implantación de Prótesis de Válvulas Cardíacas/economía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Implantación de Prótesis de Válvulas Cardíacas/tendencias , Persona de Mediana Edad , Inteligencia Artificial/economía , Inteligencia Artificial/tendencias , Prevalencia , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/economía , Estados Unidos/epidemiología , Estudios Retrospectivos , Cateterismo Cardíaco/economía , Estudios Prospectivos , Adulto , Anciano de 80 o más Años , Disparidades en Atención de Salud/economía , Disparidades en Atención de Salud/tendencias , Estudios de CohortesRESUMEN
Cangrelor, a potent intravenous P2Y12 platelet inhibitor, has demonstrated effectiveness in reducing ischemic events without a corresponding increase in severe bleeding during percutaneous coronary intervention, as evidenced by the CHAMPION-PHOENIX trial. Its off-label role as a bridging antiplatelet agent for patients facing high thrombotic risks who must temporarily stop oral P2Y12 inhibitor therapy further underscores its clinical utility. This is the first case series to shed light on the application of cangrelor in cancer patients needing to pause dual antiplatelet therapy for a range of medical interventions, marking it as a pioneering effort in this domain. The inclusion of patients with a variety of cancer types and cardiovascular conditions in this series underlines the adaptability and critical role of cangrelor in managing the dual challenges of bleeding risk and the need for uninterrupted antiplatelet protection. By offering a bridge for high-risk cancer patients who have recently undergone percutaneous coronary intervention and need to halt oral P2Y12 inhibitors temporarily, cangrelor presents a practical solution. Early findings indicate it can be discontinued safely 2-4 h before medical procedures, allowing for the effective reintroduction of oral P2Y12 inhibitors without adverse effects. This evidence calls for expanded research to validate and extend these preliminary observations, emphasizing the importance of further investigation into cangrelor's applications in complex patient care scenarios.
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PURPOSE: The purpose of this study was to evaluate safety and cardiovascular outcomes as well as overall survival of cancer patients with concomitant heart failure (HF) treated with midodrine for hypotension. METHODS: Adult patients diagnosed with cancer and HF who were treated with midodrine at a tertiary cancer center from 03/2013 to 08/2021 were identified. Demographic and clinical parameters were collected retrospectively. RESULTS: A total of 85 patients were included with a median age of 68 years (IQR: 60, 74; 33% female and 85% White). Of those, 31% had HFpEF (EF ≥ 50%), 42% HF with mildly reduced EF (HFmrEF; EF 41-49%), and 27% HFrEF (EF ≤ 40%). The most common indication for midodrine use was orthostatic hypotension (49%). Midodrine was continued for at least one month in 57% of the patients. Supine hypertension was the only side effect reported in 6% of patients. No statistically significant changes in NYHA class, guideline-directed medical therapy, cardiac biomarkers (NT-proBNP or troponin T), echocardiographic findings or cardiovascular hospitalizations were observed between patients who continued treatment with midodrine compared to those who stopped using midodrine over a median follow-up of 38 months. In the multivariable cox regression analysis, continuation of midodrine, compared to discontinuation, and use of midodrine for orthostatic hypotension, as opposed to other causes of hypotension, were not associated with an increased risk of mortality (HR 0.41, 95% CI 0.24-0.69, p < .0001; HR 0.34, 95% CI 0.18-0.64, p < .001, respectively). In contrast, elevated creatinine (> 1.3 for males and > 1.1 for females) was associated with an increased risk of mortality (HR 1.83, 95% CI 1.07-3.14). LVEF was not significantly associated with lower or higher risk of mortality. CONCLUSIONS: In our study, midodrine use in patients with cancer and HF was not associated with significant adverse effects, worse cardiovascular outcomes, or increased risk of mortality. Larger, prospective studies are needed to confirm these findings.
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AIM: To determine whether photobiomodulation (PBM) therapy could increase the depth of analgesia during endodontic therapy of teeth affected with symptomatic irreversible pulpitis. MATERIALS AND METHODS: Forty-nine patients with symptomatic irreversible pulpitis were randomized into two groups. In the laser group, before administering anesthesia, the lower molars' crowns were continuously treated with a diode laser (980 nm) for 20 s with a low-level laser tip in the buccal aspect close to the gingival margin. While the teeth of the second group who was blinded to the type of treatment received placebo treatment wherein the laser device was switched off. The visual analogue scale (VAS) was used to assess pain in both groups before the endodontic procedure, during dentin cutting, and at dropping pulp, wherein, the success was defined as no or mild pain. The Chi-square and independent sample t-tests were used to assess the data. RESULTS: During dentin cutting and pulp dropping, the group receiving the laser therapy presented with less mean pain score than the placebo group which was statistically significant. Additionally, it was observed that the need for supplementary injection was less frequent in the laser-treated group than in the placebo group (p = 0.01). CONCLUSION: The irradiation by diode laser (980 nm) prior to administration of local anesthesia appears to be useful in minimizing discomfort and additional injection during root canal therapy (RCT). CLINICAL SIGNIFICANCE: Pain management is essential for providing the best possible treatment to patients before, during, and after endodontic therapy. Adequate pain control during treatment also aids in reducing postoperative discomfort. This implies the need for additional methods to reduce discomfort during endodontic treatment; hence, adjuncts are crucial to achieving this goal. Photobiomodulation may be used as an adjuvant to reduce discomfort and supplementary injections during RCT.
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Pulpitis , Humanos , Pulpitis/terapia , Anestesia Local , Atención Odontológica , Pulpa Dental , DolorRESUMEN
BACKGROUND: There is a paucity of data regarding the comparative efficacy and safety of Mitral valve transcatheter edge-to-edge repair (MTEER) using the PASCAL or MitraClip systems for patients with mitral regurgitation (MR). METHODS: An electronic search was conducted for MEDLINE, COCHRANE, and EMBASE, through February 2023, for studies comparing the clinical outcomes of MTEER using PASCAL versus MitraClip systems among patients with severe MR. The primary study outcome was residual MR ≤ 2 at discharge. Data were pooled using a random-effects model. RESULTS: The final analysis included six studies with a total of 1581 patients, with a weighted follow-up period of 3.5 months. Two studies only included patients with degenerative MR, while the remaining studies included both degenerative and functional MR. There was no significant difference in procedure duration between MTEER with the PASCAL or MitraClip systems. There was no difference in residual MR ≤ 2 at discharge (94.7% vs. 91.9%; odds ratio [OR]: 1.44; 95% confidence interval [CI]: 0.92-2.27) or residual MR ≤ 2 at the mid-term follow-up (94.6% vs. 91.0%, p = 0.05) among the PASCAL versus MitraClip systems. There was no difference between both groups in residual MR ≤ 1 at discharge (73.1% vs. 63.8%, p = 0.12), while there was greater incidence of residual MR ≤ 1 at midterm follow-up with the PASCAL system (71.3% vs. 56.2%, p < 0.001). There was no difference between the PASCAL and MitraClip MTEER systems in technical success (97.0% vs. 97.9%, p = 0.15), procedural success (89.1% vs. 87.1%, p = 0.78), single leaflet detachment (1.8% vs. 1.4%, p = 0.55), or all-cause mortality (3.6% vs. 4.6%, p = 0.71). CONCLUSION: In this meta-analysis, we demonstrated comparable efficacy and safety between the PASCAL and MitraClip MTEER systems at short- and mid-term assessments. Randomized trials are warranted to evaluate the comparative long-term outcomes between both MTEER systems.
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Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Humanos , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/cirugía , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Resultado del Tratamiento , Cateterismo Cardíaco/efectos adversosRESUMEN
Purpose of review: The treatment of coronary artery disease (CAD) in cancer patients is an evolving landscape. Recent data emphasizes the importance of aggressive management of cardiovascular risk factors and diseases in improving cardiovascular health in this unique group of patients regardless of cancer type or stage. Recent findings: Novel cancer therapeutics such as immune therapies and proteasome inhibitors have been associated with CAD. Recent stent technologies may safely allow for shorter duration (< 6 months) of dual antiplatelet therapy post-percutaneous coronary interventions. Intracoronary imaging may be useful in the decision making process in terms of stent positioning and healing. Summary: Large registry studies have partially filled a gap left by the lack of randomized controlled trials in the treatment of CAD in cancer patients. Cardio-oncology is gaining traction as a major sub-specialty in the cardiology field given the release of the first European Society of Cardiology - Cardio-oncology guidelines in 2022.
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BACKGROUND: Previous studies have documented a negative impact of the COVID-19 pandemic on emergent percutaneous treatment of patients with ST-segment elevation myocardial infarction (STEMI), but few have examined recovery of healthcare systems in restoring prepandemic STEMI care. METHODS: Retrospective analysis was performed of data from 789 patients with STEMI from a large tertiary medical center treated with percutaneous coronary intervention between January 1, 2019, and December 31, 2021. RESULTS: For patients with STEMI presenting to the emergency department, median time from door to balloon was 37 minutes in 2019, 53 minutes in 2020, and 48 minutes in 2021 (P < .001), whereas median time from first medical contact to device changed from 70 to 82 to 75 minutes, respectively (P = .002). Treatment time changes in 2020 and 2021 correlated with median emergency department evaluation time (30 to 41 to 22 minutes, respectively; P = .001) but not median catheterization laboratory revascularization time. For transfer patients, median time from first medical contact to device changed from 110 to 133 to 118 minutes, respectively (P = .005). In 2020 and 2021, patients with STEMI had greater late presentation (P = .028) and late mechanical complications (P = .021), with nonsignificant increases in yearly in-hospital mortality (3.6% to 5.2% to 6.4%; P = .352). CONCLUSION: COVID-19 was associated with worsening STEMI treatment times and outcomes in 2020. Despite improving treatment times in 2021, in-hospital mortality had not decreased in the setting of a persistent increase in late patient presentation and associated STEMI complications.
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COVID-19 , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/terapia , Infarto del Miocardio con Elevación del ST/etiología , Estudios Retrospectivos , Pandemias , Factores de Tiempo , Intervención Coronaria Percutánea/efectos adversos , Tiempo de TratamientoRESUMEN
Magnetorheological elastomers (MREs) are smart viscoelastic materials in which their physical properties can be altered when subjected to a varying magnetic field strength. MREs consist of an elastomeric matrix mixed with magnetic particles, typically carbonyl iron particles (CIPs). The magnetic field-responsive property of MREs have led to their wide exposure in research. The potential development and commercialization of MRE-based devices requires extensive investigation to identify the essential factors that can affect their properties. For this reason, this research aims to investigate the impact of CIPs' type, concentration and coating on the rheological and mechanical properties of MREs. Isotropic MREs are fabricated with four different CIP compositions differing between hard or soft, and coated or uncoated samples. Each MRE composition have three different concentrations, which is 5%, 10%, and 20% by volume. The dynamic properties of the fabricated samples are tested by compression oscillations on a dynamic mechanical analyzer (DMA). Frequency and strain dependent measurements are performed to obtain the storage and loss modulus under different excitation frequencies and strain amplitudes. The emphasis is on the magnetorheological (MR) effect and the Payne effect which are an intrinsic characteristics of MREs. The effect of the CIPs' type, coating, and concentration on the MR and Payne effect of MREs are elucidated. Overall, it is observed that, the storage and loss modulus exhibit a strong dependence on both the frequency excitations and the strain amplitudes. Samples with hard and coated CIPs tend to have a higher MR effect than other samples. A decrease in the storage modulus and non-monotonous behavior of the loss modulus with increasing strain amplitude are observed, indicating the Payne effect. The results of this study can aid in the characterization of MREs and the proper selection of CIPs grades based on the application.
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BACKGROUND: Diabetic foot ulcer (DFU) is one of the most serious diabetic complications. DFU is an open wound that usually occurs in the foot sole due to poor blood glucose control, peripheral neuropathy, and poor circulation. The human amniotic allograft membrane is a biological wound dressing derived from the amniotic membrane. It contains amino acids, nutrients, cytokines, and growth factors that make the growth process easier. OBJECTIVE: To compare dehydrated human amnion and chorion allograft (DHACA) plus the standard of wound care (SOC) with the SOC alone. METHODS: We searched for randomized clinical trials (RCTs) on PubMed, Scopus, Cochrane, and Web of Science till April 2021 using relevant keywords. All search results were screened for eligibility. We extracted the data from the included trials and pooled them as mean difference (MD) or risk ratio (RR) with the 95% confidence interval (CI) using Review Manager software (ver. 5.4). RESULTS: The pooled effect estimate from 11 RCTs showed that DHACA was superior to SOC regarding the complete wound healing in both 6th and 12th week (RR = 3.78; 95% CI: [2.51, 5.70]; P < 0.00001) and (RR = 2.00; 95% CI: [1.67, 2.39], P < 0.00001 respectively). Also, the analysis favored the DHACA regarding the mean time to heal in the 12th-week (MD = -12.07, 95%CI: [-19.23, -4.91], P = 0.001). The wound size reduction was better with DHACA (MD = 1.18, 95%CI: [-0,10, 2.26], P = 0.03). CONCLUSION: Using DHACA with SOC is safer and more effective than using SOC alone for DFU patients.
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Diabetes Mellitus , Pie Diabético , Amnios/trasplante , Pie Diabético/terapia , Humanos , Nivel de Atención , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
Commerce has had positive impacts on the whole agri-food value chain at different stages, it was developed rapidly in rural China in the past few years. E-commerce participation can promote the use intensity of organic fertilizers (OF) and this could achieve many benefits for different stakeholders including ensuring food safety, positive environmental impacts and promoting the adoption of green production technologies. Therefore, this study has used primary data collected from 733 fruit farmers in rural China to explore the impact of e-commerce participation on fruit farmers' use intensity of (OF). Unlike previous studies investigating the dichotomous decision of (OF) adoption, this study captures the use intensity of (OF) from both input quantity and cost aspects. We employed an endogenous switching regression (ESR) model to address selectivity bias caused by observed and unobserved factors. The results show that e-commerce participation significantly increases the use intensity of (OF) in input quantity and cost by 19.48% and 29.50%, respectively. Heterogeneous analysis further reveals that compared to fruit farmers with a low e-commerce participation level, fruit farmers with a high e-commerce participation level have higher (OF) use intensity. The findings also show that risk preference, human capital, cultivated area, cooperative membership and government restraint mechanisms positively and significantly affect the probability of fruit farmers' participation in e-commerce and fruit farmers' use intensity of (OF). The results emphasize that e-commerce promotion is an efficient way to encourage farmers to adopt (OF), which help improve product quality and promote sustainable agricultural development.
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Fertilizantes , Frutas , Agricultura , China , Comercio , Agricultores , HumanosRESUMEN
Magnetorheological elastomers (MREs) are a class of emerging smart materials in which their mechanical and rheological properties can be immediately and reversibly altered upon the application of a magnetic field. The change in the MRE properties under the magnetic field is widely known as the magnetorheological (MR) effect. Despite their inherent viscoelastic property-change characteristics, there are disadvantages incorporated with MREs, such as slow response time and the suspension of the magnetic particles in the elastomer matrix, which depress their MR effect. This study investigates the feasibility of a hybrid magnetorheological elastomer-fluid (MRE-F) for longitudinal vibration isolation. The hybrid MRE-F is fabricated by encapsulating MR fluid inside the elastomer matrix. The inclusion of the MR fluid can enhance the MR effect of the elastomer by providing a better response to the magnetic field and, hence, can improve the vibration isolation capabilities. For this purpose, an MRE-based coupling is developed, and isolation performance is investigated in terms of the linear transmissibility factor. The performance of the hybrid MRE-F was compared against two different MRE samples. The results show that further enhancement of MR-effect in MREs is possible by including MR fluid inside the elastomer. The hybrid MRE-F exhibited better stiffness change with the current increase and recorded the highest value of 55.911 N/mm. The transmissivity curves revealed that the MRE-F contributed to a broader shift in the natural frequency with a 7.2 Hz overall shift at 8.9 mT. The damping characteristics are higher in MRE-F, recording the highest percentage increase in damping with 33.04%. Overall, the results reveal the promising potential of hybrid MRE-F in developing MRE-based coupling for longitudinal vibration isolation.
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Introduction: This study examined the role of echocardiographic and cardiac histomorphology parameters in predicting mortality in patients with cardiac AL amyloidosis. Methods: Patients with endomyocardial biopsy-proven cardiac AL amyloidosis treated at MD Anderson Cancer Center between 6/2011 and 6/2020 were identified. Stored echocardiographic images and endomyocardial biopsy samples were processed for myocardial strain analysis and a detailed histomorphology characterization. Results: Of 43 patients; 44% were women and 63% white. Median age was 65 years; 51% underwent stem cell transplantation (SCT). Thirty patients (70%) died during follow up (median follow up: 4.1 years). Lower LA strain (<13.5%) and absence of SCT as a time-varying covariate were significantly associated with increased risk of death in the multivariate cox regression analysis. Higher LV mass and lower RV tricuspid annular plane systolic excursion were associated with increased odds of having ≥5% interstitial amyloid deposition on biopsy in the multivariate logistic regression analysis. Conclusion: Lower LA strain independently predicted mortality in our cohort, and its performance in the routine assessment of AL amyloidosis may be beneficial. Furthermore, SCT for cardiac AL amyloidosis was associated with improved OS. These findings need to be confirmed by larger studies in the era of contemporary systemic therapies.
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BACKGROUND: Although prior national reports have identified trends in the underutilization of transcatheter aortic valve replacement (TAVR) in Afro-American and Latino populations, racial and ethnic healthcare disparities in TAVR use in the State of Connecticut have not been previously reported. METHODS: We conducted a retrospective analysis of 1461 patients undergoing TAVR at our institute between from 2012 to 2020. Baseline demographics, procedural characteristics, clinical outcomes, median incomes and insurance coverage were compared between 1417 Caucasian and 44 minority patients, including 23 patients designated as Afro-American and 10 designated as Latino. Demographics of TAVR utilization at our institution were further compared to 6 additional Connecticut TAVR centers using Connecticut Hospital Association (CHA) ChimeData detailing hospital discharges for DRG 266 and 267. RESULTS: In comparison to Caucasian patients, minority cohorts were younger (75.7 ± 9.0 vs 81.5 ± 5.1 years, p < 0.001) and had more co-morbidities including diabetes (64% vs 34%, p < 001), coronary artery disease (95% vs 78%, p = 0.039), end stage renal disease requiring dialysis (9% vs 3%, p = 0.009) and atrial fibrillation (77% vs 62%, p = 0.041). The two groups did not differ with respect to other risk factors or co-morbidities, baseline echocardiographic or CTA findings, STS risk score, or procedural technique. Minority patients had a longer length of hospital stay (9.5 ± 9.0 vs 6.4 ± 6.9 days, p = 0.003), but did not differ with respect to procedural complications. Socioeconomic differences between the two groups included lower median incomes and higher rates of Medicaid or no insurance coverage for minority versus Caucasian patients. CHA ChimeData revealed a similar underutilization of TAVR in minority subgroups in the remaining 6 Connecticut TAVR centers. CONCLUSIONS: Despite statewide demographics describing 10.7% and 15.7% of the total population as Afro-American and Latino, respectively, only 3.0% of the total TAVR procedures performed at a large Connecticut health care facility were performed in minority subgroups. Despite having a higher burden of co-morbidities, minority patients had similar outcomes compared to Caucasian patients. Similar racial and ethnic disparities in TAVR utilization were confirmed statewide using CHA ChimeData.
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Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Connecticut/epidemiología , Mortalidad Hospitalaria , Humanos , Estudios Retrospectivos , Factores de Riesgo , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Resultado del Tratamiento , Estados Unidos/epidemiologíaRESUMEN
Mechanical energy is the most ubiquitous form of energy that can be harvested and converted into useful electrical power. For this reason, the piezoelectric energy harvesters (PEHs), with their inherent electromechanical coupling and high-power density, have been widely incorporated in many applications to generate power from ambient mechanical vibrations. However, one of the main challenges to the wider adoption of PEHs is how to optimize their design for maximum energy harvesting. In this paper, an investigation was conducted on the energy harvesting from seven piezoelectric patch shapes (differing in the number of edges) when attached to a non-deterministic laminated composite (single/double lamina) plate subjected to change in fiber orientation. The performance of the PEHs was examined through a coupled-field finite element (FE) model. The plate was simply supported, and its dynamics were randomized by attaching randomly distributed point masses on the plate surface in addition to applying randomly located time-harmonic point forces. The randomization of point masses and point force location on a thin plate produce non-deterministic response. The design optimization was performed by employing the ensemble-responses of the electrical potential developed across the electrodes of the piezoelectric patches. The results present the optimal fiber orientation and patch shape for maximum energy harvesting in the case of single and double lamina composite plates. The results show that the performance is optimal at 0° or 90° fiber orientation for single-lamina, and at 0°/0° and 0°/90° fiber orientations for double-lamina composites. For frequencies below 25 Hz, patches with a low number of edges exhibited a higher harvesting performance (triangular for single-lamina/quadrilateral for double-lamina). As for the broadband frequencies (above 25 Hz), the performance was optimal for the patches with a higher number of edges (dodecagonal for single-lamina/octagonal for double-lamina).
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Pakistan is an agrarian nation that is among the most vulnerable countries to climatic variations. Around 20% of its GDP is produced by agriculture, and livestock-related production contributes more than half of this value. However, few empirical studies have been conducted to determine the vulnerability and knowledge of livestock herders, and particularly the smaller herders. Comprehending individual perceptions of and vulnerabilities to climate change (CC) will enable effective formulation of CC mitigation strategies. This study intended to explore individual perceptions of and vulnerabilities to CC based on a primary dataset of 405 small livestock herders from three agro-ecological zones of Punjab. The results showed that livestock herders' perceptions about temperature and rainfall variations/patterns coincide with the meteorological information of the study locations. The vulnerability indicators show that Dera Ghazi Khan district is more vulnerable than the other two zones because of high exposure and sensitivity to CC, and lower adaptive capacity. However, all zones experience regular livelihood risks due to livestock diseases and deaths resulting from extreme climatic conditions, lower economic status, and constrained institutional and human resource capabilities, thus leading to increased vulnerability. The results indicate that low-cost local approaches are needed, such as provision of improved veterinary services, increased availability of basic equipment, small-scale infrastructure projects, and reinforcement of informal social safety nets. These measures would support cost-effective and sustainable decisions to enable subsistence livestock herders to adopt climate smart practices.
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Cambio Climático , Ganado , Agricultura , Animales , Humanos , Pakistán , PercepciónRESUMEN
INTRODUCTION: Cryptococcosis is a ubiquitous opportunistic fungal disease caused by Cryptococcus neoformans var. grubii. It has high global morbidity and mortality among HIV patients and non-HIV carriers with 99% and 95%, respectively. Furthermore, the increasing prevalence of undesired toxicity profile of antifungal, multidrug-resistant organisms and the scarcity of FDA-authorized vaccines were the hallmark in the present days. This study was undertaken to design a reliable epitope-based peptide vaccine through targeting highly conserved immunodominant heat shock 70 kDa protein of Cryptococcus neoformans var. grubii that covers a considerable digit of the world population through implementing a computational vaccinology approach. MATERIALS AND METHODS: A total of 38 sequences of Cryptococcus neoformans var. grubii's heat shock 70 kDa protein were retrieved from the NCBI protein database. Different prediction tools were used to analyze the aforementioned protein at the Immune Epitope Database (IEDB) to discriminate the most promising T-cell and B-cell epitopes. The proposed T-cell epitopes were subjected to the population coverage analysis tool to compute the global population's coverage. Finally, the T-cell projected epitopes were ranked based on their binding scores and modes using AutoDock Vina software. Results and Discussion. The epitopes (ANYVQASEK, QSEKPKNVNPVI, SEKPKNVNPVI, and EKPKNVNPVI) had shown very strong binding affinity and immunogenic properties to B-cell. (FTQLVAAYL, YVYDTRGKL) and (FFGGKVLNF, FINAQLVDV, and FDYALVQHF) exhibited a very strong binding affinity to MHC-I and MHC-II, respectively, with high population coverage for each, while FYRQGAFEL has shown promising results in terms of its binding profile to MHC-II and MHC-I alleles and good strength of binding when docked with HLA-C∗12:03. In addition, there is massive global population coverage in the three coverage modes. Accordingly, our in silico vaccine is expected to be the future epitope-based peptide vaccine against Cryptococcus neoformans var. grubii that covers a significant figure of the entire world citizens.
Asunto(s)
Cryptococcus neoformans/inmunología , Proteínas Fúngicas/inmunología , Vacunas Fúngicas/inmunología , Proteínas HSP70 de Choque Térmico/inmunología , Biología Computacional , Diseño Asistido por Computadora , Criptococosis/inmunología , Criptococosis/microbiología , Cryptococcus neoformans/genética , Mapeo Epitopo , Epítopos de Linfocito B , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , Proteínas Fúngicas/genética , Vacunas Fúngicas/administración & dosificación , Vacunas Fúngicas/genética , Antígenos HLA-C/inmunología , Antígenos HLA-C/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Humanos , Inmunogenicidad Vacunal , Simulación del Acoplamiento Molecular , Desarrollo de Vacunas/métodos , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/genética , Vacunas de Subunidad/inmunologíaRESUMEN
Climate change is severely damaging the agricultural system of many food producing regions worldwide. Small/subsistent livestock herders are the most vulnerable and less resilient group towards climatic disasters within South Asian region including Pakistan. The adoption of climate-smart practices would be beneficial for small livestock herders because of its potential to ensure food security, improve income, and sustain development simultaneously. The purpose of this paper is to investigate factors influencing small livestock herders' adaptation decisions towards changing climate by conducting field-based research. We intend to understand how institutional factors, risk perceptions, adaptations, and personal constraints affect the adaptation decisions related to climate change mitigation and choice of adaptation strategies. For this purpose, a primary data set of 405 small livestock herders from Punjab, Pakistan was used. The regression results of empirical models reveal the probability of adopting specific climate change strategies. The study results showed that zero adaptation (non-adoption) to climate change is higher when there is low literacy rate, less experience, nuclear family system, lack of institutional services, and low level of risk perception about climate change. The marginal outcome showed that the livestock herders with positive risk perception and access to the institutional services do participate more frequently in a higher number of adaptations options for economic and ecological benefits. Therefore, it is suggested that government and other development actors should strengthen institutions for trust building among local community groups and to reduce individuals' risks. Moreover, effective insurance schemes could facilitate small livestock herders to keep less but more productive livestock. The study recommends building viable and potential weather index insurance schemes which will result meaningful marginal scale benefits for smallholders. Finally, the results of major constraints suggest that it is necessary to provide awareness of climatic vulnerabilities, timely information delivery, and adequate financial facilities to offset resource constraints of livestock herders in order to adopt sustainable strategies at their farms.