275 research outputs found

    Increasing the dimension of linear systems solved by classical or quantum binary optimization: A new method to solve large linear equation systems

    Full text link
    Recently, binary optimization has become an attractive research topic due to the development of quantum computing and specialized classical systems inspired by quantum computing. These hardware systems promise to speed up the computation significantly. In this work, we propose a new method to solve linear systems written as a binary optimization problem. The procedure solves the problem efficiently and allows it to handle large linear systems. Our approach is founded on the geometry of the original linear problem and resembles the gradient conjugate method. The conjugated directions used can significantly improve the algorithm's convergence rate. We also show that a partial knowledge of the intrinsic geometry of the problem can divide the original problem into independent sub-problems of smaller dimensions. These sub-problems can then be solved using quantum or classical solvers. Although determining the geometry of the problem has an additional computational cost, it can substantially improve the performance of our method compared to previous implementations.Comment: 12 pages, 10 figure

    Molecular characterization of mosquitoes (Diptera: Culicidae) from the Colombian rainforest

    Get PDF
    A few studies have carried out the taxonomic and molecular characterization of sylvatic mosquito species in Latin America, where some species have been incriminated as vectors for arboviruses and parasites transmission. The present study reports the molecular characterization of mosquito species in the Sierra Nevada de Santa Marta, a natural ecosystem in the Northern coast of Colombia. Manual capture methods were used to collect mosquitoes, and the specimens were identified via classical taxonomy. The COI marker was used for species confirmation, and phylogenetic analysis was performed using the neighbor-joining method, with the Kimura-2-Parameters model. Aedes serratus , Psorophora ferox , Johnbelkinia ulopus , Sabethes chloropterus , Sabethes cyaneus , Wyeomyia aporonoma , Wyeomyia pseudopecten , Wyeomyia ulocoma and Wyeomyia luteoventralis were identified. We assessed the genetic variability of mosquitoes in this area and phylogenetic reconstructions allowed the identification at the species level. Classical and molecular taxonomy demonstrated to be useful and complementary when morphological characteristics are not well preserved, or the taxonomic group is not represented in public molecular databases

    The roasting process and place of cultivation influence the volatile fingerprint of Criollo cocoa from Amazonas, Peru

    Get PDF
    The Criollo cocoa bean is classified as “fine” or flavor cocoas, being perceived as aromatic or smooth with fruity, raisin, floral, spicy, nutty, molasses, and caramel notes. In the present work, gas chromatography coupled to mass spectrometry was used to study the volatile fingerprint of roasted and unroasted Criollo cocoa from four Amazon districts: Nieva, Cajaruro, Copallín and La Peca located in the Amazon Region of Peru. The results showed that the main sensory perception of cocoa is fruit, and this decreases as the roasting intensity increases. A total of 96 volatile compounds were found, of which the esters had a greater presence in the volatile fingerprint of Criollo cocoa. Propyl acetate (3.5%), acetoin acetate (1.3%) and diethyl succinate (0.8%) were found as the characteristic compounds of Criollo cocoa analyzed, which give it its fruit perception. The linalool/benzaldehyde ratio was between 0.56 and 0.89 for La Peca and Cajaruro cocoa. Principal component analysis revealed that the Criollo cocoa in each district has a different volatile fingerprint, whether it is roasted or unroasted beans. The roasting process generates a greater differentiation of the volatile fingerprint of Criollo cocoa

    Elaboración de fichas técnicas de dispositivos médicos en el marco de las evaluaciones de tecnologías sanitarias durante la pandemia por COVID-19: Una revisión de la situación a nivel mundial y reporte de la experiencia peruana

    Get PDF
    Background: Given the health emergency caused by COVID-19, the need for the use of medical devices was particularly relevant. Methodology: A non-systematic literature search was conducted to identify documents that address topics related to the development, implementation, evaluation and/or characteristics of technical datasheets for medical devices. In addition, the SAP System was reviewed for the collection and analysis of data related to pre-pandemic (2000-2019) and in-pandemic (2020-2021) procurement. Evidence: At the global level, the experiences of WHO, ECRI Institute and INAHTA were described. At the Latin American level, experiences were found in Ecuador, Colombia, Argentina, Brazil, Mexico and Panama. Finally, at the Peruvian level, the experience of EsSalud was reported, showing that, from March 6, 2020 to May 21, 2021, 47 technical specifications were prepared for medical devices, of which 41 had purchase records, and of these, 13 correspond to biomedical and complementary equipment. We prioritized the reporting of consumption information (expressed in quantities purchased) for three devices: compact pulse oximeter, high-flow oxygen therapy equipment and the oxygen concentrator (10 L/min). Conclusion: The preparation of technical sheets considers the best scientific evidence available, as well as the technical-technological aspects of the medical device. In EsSalud, its preparation has allowed the incorporation of a significant quantity and variety of biomedical equipment for the treatment of COVID-19, in addition they have been made available with recommendations for their clinical use based on the scientific evidence analyzed.IntroducciĂłn: Ante la situaciĂłn de emergencia sanitaria por la COVID-19, la necesidad de uso de dispositivos mĂ©dicos tuvo especial relevancia. MetodologĂ­a: Se realizĂł una bĂșsqueda no sistemĂĄtica de la literatura dirigida a la identificaciĂłn de documentos que aborden tĂłpicos relacionados al desarrollo, implementaciĂłn, evaluaciĂłn y/o caracterĂ­sticas de fichas tĂ©cnicas de dispositivos mĂ©dicos. AsĂ­ mismo, se revisĂł el Sistema SAP para la obtenciĂłn y anĂĄlisis de los datos relacionados a las compras antes de pandemia (2000-2019) y durante pandemia (2020-2021). Contenido: A nivel mundial, se describieron las experiencias de la OMS, Instituto ECRI e INAHTA. A nivel de LatinoamĂ©rica, se encontraron experiencias en Ecuador, Colombia, Argentina, Brasil, MĂ©xico y PanamĂĄ. Finalmente, a nivel PerĂș, se reportĂł la experiencia de EsSalud, evidenciĂĄndose que, del 6 de marzo de 2020 al 21 de mayo de 2021, se elaboraron 47 fichas tĂ©cnicas de dispositivos mĂ©dicos, de las cuales 41 figuraban con registros de compras, y de estos, 13 corresponden a equipos biomĂ©dicos y complementarios. Priorizamos el reporte de informaciĂłn del consumo (expresado en cantidades adquiridas) de tres dispositivos: pulsioxĂ­metro compacto, equipo de oxigenoterapia de alto flujo y concentrador de oxĂ­geno de 10 L/minuto. ConclusiĂłn: La elaboraciĂłn de fichas tĂ©cnicas considera la mejor evidencia cientĂ­fica disponible, asĂ­ como los aspectos tĂ©cnicos-tecnolĂłgicos propios del dispositivo mĂ©dico. En EsSalud, su elaboraciĂłn ha permitido incorporar una importante cantidad y variedad de equipos biomĂ©dicos para el tratamiento de COVID-19, ademas han sido puestos a disposiciĂłn con recomendaciones de su uso clĂ­nico sustentadas en la evidencia cientĂ­fica analizada

    Implications of the polymorphism of HLA-G on its function, regulation, evolution and disease association

    Get PDF
    The HLA-G gene displays several peculiarities that are distinct from those of classical HLA class I genes. The unique structure of the HLA-G molecule permits a restricted peptide presentation and allows the modulation of the cells of the immune system. Although polymorphic sites may potentially influence all biological functions of HLA-G, those present at the promoter and 3â€Č untranslated regions have been particularly studied in experimental and pathological conditions. The relatively low polymorphism observed in the MHC-G coding region both in humans and apes may represent a strong selective pressure for invariance, whereas, in regulatory regions several lines of evidence support the role of balancing selection. Since HLA-G has immunomodulatory properties, the understanding of gene regulation and the role of polymorphic sites on gene function may permit an individualized approach for the future use of HLA-G for therapeutic purposes

    Pros and cons of different therapeutic antibody formats for recombinant antivenom development.

    Get PDF
    Antibody technologies are being increasingly applied in the field of toxinology. Fuelled by the many advances in immunology, synthetic biology, and antibody research, different approaches and antibody formats are being investigated for the ability to neutralize animal toxins. These different molecular formats each have their own therapeutic characteristics. In this review, we provide an overview of the advances made in the development of toxin-targeting antibodies, and discuss the benefits and drawbacks of different antibody formats in relation to their ability to neutralize toxins, pharmacokinetic features, propensity to cause adverse reactions, formulation, and expression for research and development (R&D) purposes and large-scale manufacturing. A research trend seems to be emerging towards the use of human antibody formats as well as camelid heavy-domain antibody fragments due to their compatibility with the human immune system, beneficial therapeutic properties, and the ability to manufacture these molecules cost-effectively

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

    Get PDF
    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

    Get PDF
    : The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSSŸ v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity &gt; 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

    Get PDF
    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to &lt;90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], &gt;300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of &lt;15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P&lt;0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P&lt;0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years
    • 

    corecore