High Polymer Molecular Weight Yields Solar Cells with Simultaneously Improved Performance and Thermal Stability.

Simple synthetic routes, high active layer thickness tolerance as well as stable organic solar cells are relentlessly pursued as key enabling traits for the upscaling of organic photovoltaics. Here, the potential to address these issues by tuning donor polymer molecular weight is investigated. Specifically, the focus is on PTQ10, a polymer with low synthetic complexity, with number average molecular weights of 2.4, 6.2, 16.8, 52.9, and 54.4 kDa, in combination with three different non-fullerene acceptors, namely Y6, Y12, and IDIC. Molecular weight, indeed, unlocks a threefold increase in power conversion efficiency for these blends. Importantly, efficiencies above 10% for blade coated devices with thicknesses between 200 and 350 nm for blends incorporating high molecular weight donor are shown. Spectroscopic, GIWAXS and charge carrier mobility data suggest that the strong photocurrent improvement with molecular weight is related to both, improved electronic transport and polymer contribution to exciton generation. Moreover, it is demonstrated that solar cells based on high molecular weight PTQ10 are more thermally stable due to a higher glass transition temperature, thus also improving device stability.

Mid-to-far infrared tunable perfect absorption by a sub - λ/100 nanofilm in a fractal phasor resonant cavity.

Integrating an absorbing thin film into a resonant cavity is the most practical way to achieve perfect absorption of light at a selected wavelength in the mid-to-far infrared, as required to target blackbody radiation or molecular fingerprints. The cavity is designed to resonate and enable perfect absorption in the film at the chosen wavelength λ. However, in current state-of-the-art designs, a still large absorbing film thickness (∼λ/50) is needed and tuning the perfect absorption wavelength over a broad range requires changing the cavity materials. Here, we introduce a new resonant cavity concept to achieve perfect absorption of infrared light in much thinner and thus, really nanoscale films, with a broad wavelength tenability by using a single set of cavity materials. It requires a nanofilm with giant refractive index and small extinction coefficient (found in emerging semi-metals, semi-conductors and topological insulators) backed by a transparent spacer and a metal mirror. The nanofilm acts both as absorber and multiple reflector for the internal cavity waves, which after escaping follow a fractal phasor trajectory. This enables a totally destructive optical interference for a nanofilm thickness more than 2 orders of magnitude smaller than λ. With this remarkable effect, we demonstrate angle-insensitive perfect absorption in sub - λ/100 bismuth nanofilms, at a wavelength tunable from 3 to 20 µm.

[Characterization of patients who died of invasive pneumococcal disease in the child population of Bogota, Colombia]. / Caracterización de pacientes fallecidos por enfermedad neumocóccica invasiva en la poblacion infantil de Bogotá, Colombia.

INTRODUCTION: Streptococcus pneumoniae (S. pneumoniae), also known as pneumococcus, is one of the main bacteria associated with mortality in children under 2 years of age, with a morbidity and mortality incidence that varies according to demographics and exposure to risk, or protective factors. OBJECTIVE: To describe the child mortality due to invasive pneumococcal disease (IPD) between 2008 -2014 (6 years), in 8 Medical Centres in Bogotá, Colombia. PATIENTS AND METHOD: Descriptive observational case series of patients who died of IPD, aged 28 days to 18 years, in 8 tertiary care institutions in Bogota, Colombia. The study period was from 1 January 2008 to 15 January 2014. SAMPLE SIZE: 239 patients. RESULTS: A total of 239 registered cases of IPD were reviewed, showing a mortality of 8% (n 18). The mean age of patients that died was 43.7 months, with an age range from 2 to 176 months (14 years), with 66% of the cases being male. Serotypes were identified in 8 patients, finding: 6A, 6B, 10A, 14, 18C, 23B, 23F, and 35B. The most common clinical presentation of the cases was meningitis with mortality of 33% (6 cases), followed by bacteraemia without focus in 28% (5 cases), and pneumonia with 27% (5 cases). Combined clinical situations were presented, such as pneumonia and meningitis in 11% (2 cases). Two of the patients had clearly documented risk factors for IPD (asplenia and chronic respiratory disease). CONCLUSIONS: IPD mortality is particularly high in children under 2 years in male patients, especially when presented with a meningeal focus (44%). Serotyping was not possible in all patients who died, since no strain isolated was sent to the National Institute of Health. Continuous and systematic vigilance is required to evaluate the impact of vaccination and possible changes in the pattern of presentation of disease.

Serotype distribution, clinical characteristics, and antimicrobial resistance of pediatric invasive pneumococcal disease in Colombia during PCV10 mass vaccination (2017-2022).

Introduction: Invasive Pneumococcal Disease (IPD) causes significant morbidity and mortality in children under 5 y. Colombia introduced PCV10 vaccination in 2012, and the Neumocolombia network has been monitoring IPD in pediatric patients since 2008. Materials and methods: This study is a secondary analysis of a prospective cohort involving pediatric patients with IPD admitted to 17 hospitals in Colombia, from January 1st, 2017, to December 31st, 2022. We present data on serotypes (Spn), clinical characteristics, and resistance patterns. Results: We report 530 patients, 215 (40.5%) were younger than 24 months. Among these, 344 cases (64.7%) presented with pneumonia, 95 (17.9%) with primary bacteremia, 53 (10%) with meningitis, 6 (1.1%) had pneumonia and meningitis, and 32 (6%) had other IPD diagnosis. The median hospital stay was 12 days (RIQ 8-14 days), and 268 (50.6%) were admitted to the ICU, of whom 60 (11.3%) died. Serotyping was performed in 298 (56.1%). The most frequent serotypes were Spn19A (51.3%), Spn6C (7.7%), Spn3 (6.7%), Spn6A (3.6%), and Spn14 (3.6%). Of 495 (93%) isolates with known susceptibility, 46 (9.2%) were meningeal (M) and 449 (90.7%) non-meningeal (NM). Among M isolates, 41.3% showed resistance to penicillin, and 21.7% decreased susceptibility to ceftriaxone. For NM isolates, 28.2% had decreased susceptibility to penicilin, and 24.2% decreased susceptibility to ceftriaxone. Spn19A showed the highest resistant to penicillin at 47% and was linked to multiresistance. Conclusion: The prevalence of PCV10-included serotypes decreased, while serotypes 19A and 6C increased, with Spn19A being associated with multiresistance. These findings had played a crucial role in the decision made by Colombia to modify its immunization schedule by switching to PCV13 in July 2022.

Atypical Rasmussen's Encephalitis.

A three-year-old female patient was admitted to our institution due to subacute fever, intermittent vomiting, persistent bilateral mydriasis after cycloplegia, right central facial palsy, and mild right hemiparesis with hyperreflexia. Brain MRI shows encephalitis in frontal, parietal, insular, and left putamen course and loss of cortical volume and white matter of the entire left hemisphere which are features described in Rasmussen's encephalitis (RE). Therapy with intravenous methylprednisolone bolus was initiated, with adequate clinical response. We consider in this case the diagnosis of atypical RE by imaging criteria in the subacute stage. There are few reports of atypical RE without epilepsy or continuous partial epilepsy. Our purpose is to present a case of a patient with RE images without epilepsy seizures and review the diagnostic and therapeutic approach of RE.

Risk factors for cardiovascular diseases during medical academic training.

BACKGROUND: Cardiovascular diseases (CVDs) are the main cause of morbidity and mortality in the world. Previous studies disagree about the prevalence of cardiovascular risk factors (CVRFs) among medical students. OBJECTIVES: Determine the CVRFs prevalence in medical students. Compare the FRCVs percentage from initial and advanced course stages. Evaluate whether the CVRFs percentage was similar to that from population in the same age group, as previously described in another studies. METHOD: This is a cross-sectional observational study that evaluated the CVRFs prevalence in medical students using a semi-structured questionnaire, in addition to physical examination and laboratory tests. For statistical analysis, statistical package for the social science software (SPSS, version 22.0) was used. RESULTS: 115 students were evaluated: 74.8%, female; mean age, 22.4±3.1 years. In the general sample was found altered dosages of total cholesterol (27.0%), high density lipoprotein cholesterol (HDL, 5.2%), triglycerides (12.2%), low density lipoprotein cholesterol (LDL, 8.7%), fasting glucose (4.3%), overweight (17.4%), obesity (5.2%), inadequate physical activity (45.2%), family history of cardiovascular disease (44.3%), stress (68.7%), anxiety (83.5%), insomnia (28.7%), sleep deprivation (60.0%), alcohol use (91.3%) and low cardiovascular risk (100.0%). The average score from PSS-14 questionnaire showed greater stress in the basic (27.0±6.7) and clinical cycle (28.3±7.1) and less stress in the internship (22.3±6.4). There was a statistical difference between the clinical cycle and internship (P < 0.05). During internship, there was a lower association between stress and graduation (33.3%), especially when compared to the clinical cycle (75.4%) (P < 0.01; ra=2.9). CONCLUSION: CVRFs exposure and the risk of negative cardiovascular outcomes are lower in medical students when compared to young adult population. Suggestive of medical training contributes to self-care, health promotion, stress reduction and disease prevention, reducing the cardiovascular diseases prevalence, especially in the internship.

Confirmed cases of COVID-19 after vaccination against COVID in health personnel in Bogotá, Colombia.

OBJECTIVE: The present study aims to estimate the frequency of COVID 19 infections in vaccinated health personnel at a Los CObos Medical Center in Bogotá, Colombia. The percentage of people positive to the PCR test and their clinical characteristics were analyzed. METHODS: We performed a cross-sectional study. The primary study variable was the COVID vaccination registry. We analyzed sex, age, signs, and symptoms. Multivariable logistic regression was applied to assess changes over time and to identify variables associated with vaccination in target groups. RESULTS: A cohort of 999 people working at Los Cobos Medical Center and followed from March to August 2021. The average age of this cohort was 37.0 years (devest = 10.5 years), 67.7 % were women. Two hundred eleven physicians, 287 nurses, 305 assistants, and 196 clerks follows. In addition, 8.4 % to be PCR positive after vaccination. The average age was 36.0 (devest = 23.4 years), 59 women and 25 men. Of these, 15 were administrative, 14 were doctors, 29 nurses, and 26 nursing assistants. The vaccination status found that 21.4 % do not vaccinates, 7.1 % were partially vaccinated, and 71.4 % with a complete schedule. When questioned about symptoms in these patients, 4.0 % were symptomatic, and 5.9 % were asymptomatic. CONCLUSIONS: A recent epidemiological study involving 12,364 health workers with a mean age of 38 years quantifies the protection in six months from the vaccine. The presence of antibodies was associated with 83 % protection against active SARS-CoV-2 infection (PCR positivity during the study period), which confirms the existence of protective Immunity at levels comparable to those obtained by the approved vaccines; our study found effectiveness of 92.6 %. Higher than that found in this study, possibly explained by the characteristics of the individuals included.

Enhanced Organic Electrochemical Transistor Performance of Donor-Acceptor Conjugated Polymers Modified with Hybrid Glycol/Ionic Side Chains by Postpolymerization Modification.

Emergent bioelectronic technologies are underpinned by the organic electrochemical transistor (OECT), which employs an electrolyte medium to modulate the conductivity of its organic semiconductor channel. Here we utilize postpolymerization modification (PPM) on a conjugated polymer backbone to directly introduce glycolated or anionic side chains via fluoride displacement. The resulting polymers demonstrated increased volumetric capacitances, with subdued swelling, compared to their parent polymer in p-type enhancement mode OECTs. This increase in capacitance was attributed to their modified side chain configurations enabling cationic charge compensation for thin film electrochemical oxidation, as deduced from electrochemical quartz crystal microbalance measurements. An overall improvement in OECT performance was recorded for the hybrid glycol/ionic polymer compared to the parent, owing to its low swelling and bimodal crystalline orientation as imaged by grazing-incidence wide-angle X-ray scattering, enabling its high charge mobility at 1.02 cm2·V-1·s-1. Compromised device performance was recorded for the fully glycolated derivative compared to the parent, which was linked to its limited face-on stacking, which hindered OECT charge mobility at 0.26 cm2·V-1·s-1, despite its high capacitance. These results highlight the effectiveness of anionic side chain attachment by PPM as a means of increasing the volumetric capacitance of p-type conjugated polymers for OECTs, while retaining solid-state macromolecular properties that facilitate hole transport.

Use of complementary and alternative medicine by cancer patients in Colombia.

BACKGROUND: The use of complementary and alternative medicines (CAM) among cancer patients varies greatly. The available data suggest an increasing use of CAM over time and a higher prevalence in low- and middle-income countries. However, no reliable data are available from Latin America. Accordingly, we examined the prevalence of CAM use among cancer patients from six Colombian regions. METHODS: We conducted a survey on cancer patients attending comprehensive cancer centres in six capital cities from different regions. The survey was designed based on a literature review and information gathered through focus groups on CAM terminology in Colombia. Independent random samples of patients from two comprehensive cancer centres in every city were obtained. Patients 18 years and older with a histopathological diagnosis of cancer undergoing active treatment were eligible. The prevalence of CAM use is reported as a percentage with the corresponding confidence interval. CAM types are reported by region. The sociodemographic and clinical characteristics of CAM users and non-users were compared using Chi square and t tests. RESULTS: In total, 3117 patients were recruited. The average age 59.6 years old, and 62.8% were female. The prevalence of CAM use was 51.7%, and compared to non-users, CAM users were younger, more frequently women, affiliated with the health insurance plan for low-income populations and non-Catholic. We found no differences regarding the clinical stage or treatment modality, but CAM users reported more treatment-related side effects. The most frequent types of CAM were herbal products, specific foods and vitamins, and individually, soursop was the most frequently used product. Relevant variability between regions was observed regarding the prevalence and type of CAM used (range: 36.6% to 66.7%). The most frequent reason for using CAM was symptom management (30.5%), followed by curative purposes (19.5%). CONCLUSIONS: The prevalence of CAM use among cancer patients in Colombia is high in general, and variations between regions might be related to differences in cultural backgrounds and access to comprehensive cancer care. The most frequently used CAM products and practices have little scientific support, suggesting the need to enhance integrative oncology research in the country.

Colombian Adaptation of the Self-Compassion Scale (SCS).

BACKGROUND: Self-Compassion is crucial for assessing how people relate to their suffering in moments of personal difficulty. The objective of this study was to check the psychometric properties of the Self-Compassion Scale (SCS) in a Colombian sample. METHOD: The Spanish version of the SCS was adapted to the Colombian context via a content validity technique. This version was administered to 751 Colombians from the general community. Psychometric analysis was performed using R studio packages. RESULTS: 7 models were tested, the best fit was found for the bifactor ESEM model (χ2/df = 0.86, CFI = 1, TLI= 1, RMSEA= 0.00, SRMR= 0.01). This model produced optimal reliability indices (ωh = 0.83, FD= 0.93, H= 0.96). CONCLUSIONS: The study produced initial psychometric evidence of the structure of the SCS in Colombia, with evidence of a general factor in the bifactor ESEM model. More research is needed to justify the complete usage of the SCS in the country.