Acute kidney injury and point-of-care ultrasound in liver cirrhosis: redefining hepatorenal syndrome.

Acute kidney injury (AKI) in patients with cirrhosis is a diagnostic challenge due to multiple and sometimes overlapping possible etiologies. Many times, diagnosis cannot be made based on case history, physical examination or laboratory data, especially when the nephrologist is faced with AKI with a hemodynamic basis, such as hepatorenal syndrome. In addition, the guidelines still include generalized recommendations regarding withdrawal of diuretics and plasma volume expansion with albumin for 48 h, which may be ineffective and counterproductive and may have iatrogenic effects, such as fluid overload and acute cardiogenic pulmonary edema. For this reason, the use of new tools, such as hemodynamic point-of-care ultrasound (PoCUS), allows us to phenotype volume status more accurately and ultimately guide medical treatment in a noninvasive, rapid and individualized manner.

MyTrack+: Human-centered design of an mHealth app to support long-term weight loss maintenance.

A growing body of research has focused on the utility of adaptive intervention models for promoting long-term weight loss maintenance; however, evaluation of these interventions often requires customized smartphone applications. Building such an app from scratch can be resource-intensive. To support a novel clinical trial of an adaptive intervention for weight loss maintenance, we developed a companion app, MyTrack+, to pair with a main commercial app, FatSecret (FS), leveraging a user-centered design process for rapid prototyping and reducing software engineering efforts. MyTrack+ seamlessly integrates data from FS and the BodyTrace smart scale, enabling participants to log and self-monitor their health data, while also incorporating customized questionnaires and timestamps to enhance data collection for the trial. We iteratively refined the app by first developing initial mockups and incorporating feedback from a usability study with 17 university students. We further improved the app based on an in-the-wild pilot study with 33 participants in the target population, emphasizing acceptance, simplicity, customization options, and dual app usage. Our work highlights the potential of using an iterative human-centered design process to build a companion app that complements a commercial app for rapid prototyping, reducing costs, and enabling efficient research progress.

OCTOPUS: Disk-based, Multiplatform, Mobile-friendly Metagenomics Classifier.

Portable genomic sequencers such as Oxford Nanopore's MinION enable real-time applications in both clinical and environmental health, e.g., detection of bacterial outbreaks. However, there is a bottleneck in the downstream analytics when bioinformatics pipelines are unavailable, e.g., when cloud processing is unreachable due to absence of Internet connection, or only low-end computing devices can be carried on site. For instance, metagenomics classifiers usually require a large amount of memory or specific operating systems/libraries. In this work, we present a platform-friendly software for portable metagenomic analysis of Nanopore data, the Oligomer-based Classifier of Taxonomic Operational and Pan-genome Units via Singletons (OCTOPUS). OCTOPUS is written in Java, reimplements several features of the popular Kraken2 and KrakenUniq software, with original components for improving metagenomics classification on incomplete/sampled reference databases (e.g., selection of bacteria of public health priority), making it ideal for running on smartphones or tablets. We indexed both OCTOPUS and Kraken2 on a bacterial database with ~4,000 reference genomes, then simulated a positive (bacterial genomes from the same species, but different genomes) and two negative (viral, mammalian) Nanopore test sets. On the bacterial test set OCTOPUS yielded sensitivity and precision comparable to Kraken2 (94.4% and 99.8% versus 94.5% and 99.1%, respectively). On non-bacterial sequences (mammals and viral), OCTOPUS dramatically decreased (4- to 16-fold) the false positive rate when compared to Kraken2 (2.1% and 0.7% versus 8.2% and 11.2%, respectively). We also developed customized databases including viruses, and the World Health Organization's set of bacteria of concern for drug resistance, tested with real Nanopore data on an Android smartphone. OCTOPUS is publicly available at https://github.com/DataIntellSystLab/OCTOPUS and https://github.com/Ruiz-HCI-Lab/OctopusMobile.

Precision medicine: "Point of Care Ultrasound" (PoCUS) in the diagnostic approach to the patient with hyponatremia.

Hyponatremia is a multifactorial disorder defined as a decrease in plasma sodium concentration. Its differential diagnosis requires an adequate evaluation of the extracellular volume (ECV). However, ECV determination, simply based on the clinical history, vital signs, physical examination, and laboratory findings can leads to misdiagnosis and inappropriate treatment. The use of Point-of-Care Ultrasound (POCUS), through the combination of Lung Ultrasound (LUS), Venous Excess UltraSound (VExUS) and Focused Cardiac Ultrasound (FoCUS), allows a much more accurate holistic assessment of the patient's ECV status in combination with the other parameters.

A low-burden, self-weighing intervention to prevent weight gain in adults with obesity who do not enroll in comprehensive treatment.

Background: For individuals who are eligible but unlikely to join comprehensive weight loss programs, a low burden self-weighing intervention may be a more acceptable approach to weight management. Methods: This was a single-arm feasibility trial of a 12-month self-weighing intervention. Participants were healthcare patients with a BMI ≥25 kg/m2 with a weight-related comorbidity or a BMI >30 kg/m2 who reported lack of interest in joining a comprehensive weight loss program, or did not enroll in a comprehensive program after being provided program information. In the self-weighing intervention, participants were asked to weigh themselves daily on a cellular connected scale and were sent text messages every other week with tailored weight change feedback, including messages encouraging use of comprehensive programs if weight gain occurred. Results: Of 86 eligible patients, 39 enrolled (45.3%) in the self-weighing intervention. Self-weighing occurred on average 4.6 days/week (SD = 1.4). At 12 months, 12 participants (30.8%) lost ≥3% baseline weight, 11 (28.2%) experienced weight stability (±3% baseline), 6 (15.4%) gained ≥3% of baseline weight, and 10 (25.6%) did not have available weight data to evaluate. Three participants reported joining a weight loss program during the intervention (7.7%). Participants reported high intervention satisfaction in quantitative ratings (4.1 of 5), and qualitative interviews identified areas of satisfaction (e.g., timing and content of text messages) and areas for improvement (e.g., increasing personalization of text messages). Conclusion: A low-burden self-weighing intervention can reach adults with overweight/obesity who would be unlikely to engage in comprehensive weight loss programs; the efficacy of this intervention for preventing weight gain should be further evaluated in a randomized trial.

Clinical inertia in newly diagnosed type 2 diabetes mellitus among patients attending selected healthcare institutions in Colombia.

BACKGROUND: The burden of disease of diabetes in Colombia have increased in the last decades. Secondary prevention is crucial for diabetes control. Many patients already treated remain with poor glycemic control and without timely and appropriate treatment intensification. This has been called in the literature as Clinical Inertia. Updated information regarding clinical inertia based on the Colombian diabetes treatment guidelines is needed. OBJECTIVE: To measure the prevalence of clinical inertia in newly diagnosed Type 2 Diabetes Mellitus (T2DM) patients in healthcare institutions in Colombia, based on the recommendations of the current official guidelines. METHODS: An observational and retrospective cohort study based on databases of two Health Medical Organizations (HMOs) in Colombia (one from subsidized regimen and one from contributory regimen) was conducted. Descriptive analysis was performed to summarize demographic and clinical information. Chi-square tests were used to assess associations between variables of interest. RESULTS: A total of 616 patients with T2DM (308 for each regimen) were included. Median age was 61 years. Overall clinical inertia was 93.5% (87.0% in contributory regimen and 100% in subsidized regimen). Patients with Hb1Ac ≥ 8% in the subsidized regimen were more likely to receive monotherapy than patients in the contributory regimen (OR 2.33; 95% CI 1.41-3.86). CONCLUSIONS: In this study, the prevalence of overall clinical inertia was higher in the subsidized regime than in the contributory regime (100% vs 87%). Great efforts have been made to equalize the coverage between the two systems, but this finding is worrisome with respect to the difference in quality of the health care provided to these two populations. This information may help payers and clinicians to streamline strategies for reducing clinical inertia and improve patient outcomes.

Assessing workload in using electromyography (EMG)-based prostheses.

Using prosthetic devices requires a substantial cognitive workload. This study investigated classification models for assessing cognitive workload in electromyography (EMG)-based prosthetic devices with various types of input features including eye-tracking measures, task performance, and cognitive performance model (CPM) outcomes. Features selection algorithm, hyperparameter tuning with grid search, and k-fold cross-validation were applied to select the most important features and find the optimal models. Classification accuracy, the area under the receiver operation characteristic curve (AUC), precision, recall, and F1 scores were calculated to compare the models' performance. The findings suggested that task performance measures, pupillometry data, and CPM outcomes, combined with the naïve bayes (NB) and random forest (RF) algorithms, are most promising for classifying cognitive workload. The proposed algorithms can help manufacturers/clinicians predict the cognitive workload of future EMG-based prosthetic devices in early design phases.Practitioner summary: This study investigated the use of machine learning algorithms for classifying the cognitive workload of prosthetic devices. The findings suggested that the models could predict workload with high accuracy and low computational cost and could be used in assessing the usability of prosthetic devices in the early phases of the design process.Abbreviations: 3d: 3 dimensional; ADL: Activities for daily living; ANN: Artificial neural network; AUC: Area under the receiver operation characteristic curve; CC: Continuous control; CPM: Cognitive performance model; CPM-GOMS: Cognitive-Perceptual-Motor GOMS; CRT: Clothespin relocation test; CV: Cross validation; CW: Cognitive workload; DC: Direct control; DOF: Degrees of freedom; ECRL: Extensor carpi radialis longus; ED: Extensor digitorum; EEG: Electroencephalogram; EMG: Electromyography; FCR: Flexor carpi radialis; FD: Flexor digitorum; GOMS: Goals, Operations, Methods, and Selection Rules; LDA: Linear discriminant analysis; MAV: Mean absolute value; MCP: Metacarpophalangeal; ML: Machine learning; NASA-TLX: NASA task load index; NB: Naïve Bayes; PCPS: Percent change in pupil size; PPT: Purdue Pegboard Test; PR: Pattern recognition; PROS-TLX: Prosthesis task load index; RF: Random forest; RFE: Recursive feature selection; SHAP: Southampton hand assessment protocol; SFS: Sequential feature selection; SVC: Support vector classifier.

Predicting high-risk periods for weight regain following initial weight loss.

OBJECTIVE: The aim of this study was to develop a predictive algorithm of "high-risk" periods for weight regain after weight loss. METHODS: Longitudinal mixed-effects models and random forest regression were used to select predictors and develop an algorithm to predict weight regain on a week-to-week basis, using weekly questionnaire and self-monitoring data (including daily e-scale data) collected over 40 weeks from 46 adults who lost ≥5% of baseline weight during an initial 12-week intervention (Study 1). The algorithm was evaluated in 22 adults who completed the same Study 1 intervention but lost <5% of baseline weight and in 30 adults recruited for a separate 30-week study (Study 2). RESULTS: The final algorithm retained the frequency of self-monitoring caloric intake and weight plus self-report ratings of hunger and the importance of weight-management goals compared with competing life demands. In the initial training data set, the algorithm predicted weight regain the following week with a sensitivity of 75.6% and a specificity of 45.8%; performance was similar (sensitivity: 81%-82%, specificity: 30%-33%) in testing data sets. CONCLUSIONS: Weight regain can be predicted on a proximal, week-to-week level. Future work should investigate the clinical utility of adaptive interventions for weight-loss maintenance and develop more sophisticated predictive models of weight regain.

Consenso de expertos sobre la eficacia clínica y directrices sobre la terapia de oxígeno transdérmico continuo para la cicatrización de las heridas complejas o difíciles de cicatrizar.

INTRODUCTION: Oxygen is pivotal for wound healing. Its lack or hypoxia can delay this process, especially in individuals with comorbidities, potentially resulting in complex or hard-to-heal wounds. The Colombian Association of Diabetes (ACD) and the Colombian Association of Internal Medicine (ACMI) collaborated with a diverse group of experts to provide recommendations on the efficacy and best practices of continuous transdermal oxygen therapy (TOTc) in the care of such wounds. METHOD: A modified Delphi technique was employed to obtain controlled feedback and responses. Experts from various disciplines engaged in reviewing and discussing numerous relevant scientific studies, focusing on the role of TOTc in treating chronic ulcers. RESULTS: Continuous transdermal oxygen therapy has proven to be an effective and safe treatment for chronic and/or hard-to-heal ulcers. This therapy directly addresses the wound's oxygen deficiency, providing an environment conducive to healing. Significant benefits were observed, including the acceleration of the healing process, wound size reduction, and an enhancement in patient quality of life. Its efficacy was found across various ulcer etiologies, underscoring its therapeutic versatility. CONCLUSIONS: Continuous transdermal oxygen therapy is effective and safe for treating chronic and hard-to-heal ulcers. It's crucial to address each case individually and through a multidisciplinary approach to maximize this therapy's benefits. Both evidence and clinical experience back its utility across a variety of ulcer etiologies.

RESUMEN: Introducción: El oxígeno es esencial en la cicatrización de heridas. Su ausencia o hipoxia puede retrasar este proceso, especialmente en individuos con comorbilidades, lo que podría resultar en heridas complejas o de difícil cicatrización. La Asociación Colombiana de Diabetes (ACD) y la Asociación Colombiana de Medicina Interna (ACMI) se unieron con un grupo diverso de expertos para brindar recomendaciones sobre la eficacia y práctica de la terapia de oxígeno transdérmico continuo (TOTc) en el cuidado de estas heridas. Método: Se utilizó la técnica Delphi modificada para obtener respuestas y retroalimentación controlada. Expertos de diversas disciplinas participaron en la revisión y discusión de numerosos estudios científicos relevantes, centrados en el papel de la TOTc en el tratamiento de úlceras crónicas. Resultados: El oxígeno transdérmico continuo ha demostrado ser una terapia eficaz y segura en el tratamiento de úlceras crónicas y/o de difícil cicatrización. Esta terapia aborda directamente la deficiencia de oxígeno en la herida, proporcionando un entorno propicio para la curación. Se observaron beneficios significativos, incluyendo aceleración del proceso de cicatrización, reducción del tamaño de la herida y mejora en la calidad de vida del paciente. Se encontró eficacia en diversas etiologías de úlceras, subrayando su versatilidad terapéutica. Conclusiones: La terapia de oxígeno transdérmico continuo es eficaz y segura para tratar úlceras crónicas y de difícil cicatrización. Es vital abordar cada caso de manera individualizada y mediante un enfoque multidisciplinario para maximizar los beneficios de esta terapia. La evidencia y experiencia clínica respaldan su utilidad en diversas etiologías de úlceras. Palabras clave: Terapia de oxígeno transdérmico continuo, Oxígeno, Pie diabético, Cicatrización de heridas, Cuidado de heridas, Úlceras vasculares, Lesiones por presión, Hipoxia, Infección.

Superior Thermoelectric Performance of SiGe Nanowires Epitaxially Integrated into Thermal Micro-Harvesters.

Semiconductor nanowires have demonstrated fascinating properties with applications in a wide range of fields, including energy and information technologies. Particularly, increasing attention has focused on SiGe nanowires for applications in a thermoelectric generation. In this work, a bottom-up vapour-liquid-solid chemical vapour Deposition methodology is employed to integrate heavily boron-doped SiGe nanowires on thermoelectric generators. Thermoelectrical properties -, i.e., electrical and thermal conductivities and Seebeck coefficient - of grown nanowires are fully characterized at temperatures ranging from 300 to 600 K, allowing the complete determination of the Figure-of-merit, zT, with obtained values of 0.4 at 600 K for optimally doped nanowires. A correlation between doping level, thermoelectric performance, and elemental distribution is established employing advanced elemental mapping (synchrotron-based nano-X-ray fluorescence). Moreover, the operation of p-doped SiGe NWs integrated into silicon micromachined thermoelectrical generators is shown over standalone and series- and parallel-connected arrays. Maximum open circuit voltage of 13.8 mV and power output as high as 15.6 µW cm-2 are reached in series and parallel configurations, respectively, operating upon thermal gradients generated with hot sources at 200 °C and air flows of 1.5 m s-1 . These results pave the way for direct application of SiGe nanowire-based micro-thermoelectric generators in the field of the Internet of Things.

Analytic Review of Using Augmented Reality for Situational Awareness.

Situational awareness is the perception and understanding of the surrounding environment. Maintaining situational awareness is vital for performance and error prevention in safety critical domains. Prior work has examined applying augmented reality (AR) to the context of improving situational awareness, but has mainly focused on the applicability of using AR rather than on information design. Hence, there is a need to investigate how to design the presentation of information, especially in AR headsets, to increase users' situational awareness. We conducted a Systematic Literature Review to research how information is currently presented in AR, especially in systems that are being utilized for situational awareness. Comparing current presentations of information to existing design recommendations aided in identifying future areas of design. In addition, this survey further discusses opportunities and challenges in applying AR to increasing users' situational awareness.

Parents' Perception of Barriers to the Comprehensive Management of Children With Cleft Lip and Palate in Bogota, Colombia.

OBJECT: To identify the perception of barriers to the comprehensive management of cleft lip and palate (CLP) by parents/caregivers of Colombian children with this condition. SETTING AND SAMPLE POPULATION: Fifty parents/caregivers of children with CLP under 12 years attending a center specialized in the management of craniofacial congenital conditions in Bogota, Colombia. MATERIALS AND METHODS: This study consisted of 2 phases: a quantitative phase (descriptive cross-sectional) and a qualitative phase (focus group [FG]). Chi-square and Fisher exact tests were used to analyze the association variables. The barriers and alternative ways to overcome barriers were analyzed in the FG. RESULTS: Comprehensive management was mostly defined as access to multiple treatments (54%), and this concept was expanded in the FG toward understanding CLP at all levels. Monoparental families spend their income on treatments (29%) than nuclear families (0%) (P = .001). All parents with high education levels were familiar with healthcare centers specialized in CLP as opposed to 66.7% of parents with basic primary education (P < .05). Regarding the timeliness of appointments, 12.2% of parents earning between 1 and 2 minimum wages reported some kind of difficulty, whereas those earning less than one minimum wage reported difficulties in 66.7% of cases (P = .046). CONCLUSIONS: All participants reported barriers, which increased or decreased depending on their socioeconomic status. The FG allowed the discussion of alternatives to overcome barriers, such as structural, solidarity, and self-management actions.

ggMOB: Elucidation of genomic conjugative features and associated cargo genes across bacterial genera using genus-genus mobilization networks.

Horizontal gene transfer mediated by conjugation is considered an important evolutionary mechanism of bacteria. It allows organisms to quickly evolve new phenotypic properties including antimicrobial resistance (AMR) and virulence. The frequency of conjugation-mediated cargo gene exchange has not yet been comprehensively studied within and between bacterial taxa. We developed a frequency-based network of genus-genus conjugation features and candidate cargo genes from whole-genome sequence data of over 180,000 bacterial genomes, representing 1,345 genera. Using our method, which we refer to as ggMOB, we revealed that over half of the bacterial genomes contained one or more known conjugation features that matched exactly to at least one other genome. Moreover, the proportion of genomes containing these conjugation features varied substantially by genus and conjugation feature. These results and the genus-level network structure can be viewed interactively in the ggMOB interface, which allows for user-defined filtering of conjugation features and candidate cargo genes. Using the network data, we observed that the ratio of AMR gene representation in conjugative versus non-conjugative genomes exceeded 5:1, confirming that conjugation is a critical force for AMR spread across genera. Finally, we demonstrated that clustering genomes by conjugation profile sometimes correlated well with classical phylogenetic structuring; but that in some cases the clustering was highly discordant, suggesting that the importance of the accessory genome in driving bacterial evolution may be highly variable across both time and taxonomy. These results can advance scientific understanding of bacterial evolution, and can be used as a starting point for probing genus-genus gene exchange within complex microbial communities that include unculturable bacteria. ggMOB is publicly available under the GNU licence at https://ruiz-hci-lab.github.io/ggMOB/.

Spatially Resolved Dynamics of Cobalt Color Centers in ZnO Nanowires.

The dynamics of color centers, being a promising quantum technology, is strongly dependent on the local environment. A synergistic approach of X-ray fluorescence analysis and X-ray excited optical luminescence (XEOL) using a hard X-ray nanoprobe is applied. The simultaneous acquisition provides insights into compositional and functional variations at the nanoscale demonstrating the extraordinary capabilities of these combined techniques. The findings on cobalt doped zinc oxide nanowires show an anticorrelation between the band edge emission of the zinc oxide host and the intra-3d cobalt luminescence, indicating two competing recombination paths. Moreover, time-resolved XEOL measurements reveal two exponential decays of the cobalt luminescence. The fast and newly observed one can be attributed to a recombination cascade within the cobalt atom, resulting from direct excitation. Thus, this opens a new fast timescale for potential devices based on cobalt color centers in ZnO nanowires in photonic circuits.

KARGAMobile: Android app for portable, real-time, easily interpretable analysis of antibiotic resistance genes via nanopore sequencing.

Nanopore technology enables portable, real-time sequencing of microbial populations from clinical and ecological samples. An emerging healthcare application for Nanopore includes point-of-care, timely identification of antibiotic resistance genes (ARGs) to help developing targeted treatments of bacterial infections, and monitoring resistant outbreaks in the environment. While several computational tools exist for classifying ARGs from sequencing data, to date (2022) none have been developed for mobile devices. We present here KARGAMobile, a mobile app for portable, real-time, easily interpretable analysis of ARGs from Nanopore sequencing. KARGAMobile is the porting of an existing ARG identification tool named KARGA; it retains the same algorithmic structure, but it is optimized for mobile devices. Specifically, KARGAMobile employs a compressed ARG reference database and different internal data structures to save RAM usage. The KARGAMobile app features a friendly graphical user interface that guides through file browsing, loading, parameter setup, and process execution. More importantly, the output files are post-processed to create visual, printable and shareable reports, aiding users to interpret the ARG findings. The difference in classification performance between KARGAMobile and KARGA is minimal (96.2% vs. 96.9% f-measure on semi-synthetic datasets of 1 million reads with known resistance ground truth). Using real Nanopore experiments, KARGAMobile processes on average 1 GB data every 23-48 min (targeted sequencing - metagenomics), with peak RAM usage below 500MB, independently from input file sizes, and an average temperature of 49°C after 1 h of continuous data processing. KARGAMobile is written in Java and is available at https://github.com/Ruiz-HCI-Lab/KargaMobile under the MIT license.

Invasive Pneumococcal Disease Characterization in Adults and Subgroups aged < 60 years and ≥ 60 years in Bogota, Colombia.

Background: There is scarce information on the burden of invasive pneumococcal disease (IPD) among adults in low- and middle-income countries. This study aimed to describe the clinical outcomes and microbiological characteristics associated with IPD in adults and subgroups aged 18-59 years and ≥60 years in Colombia. Methods: A retrospective chart review study was conducted in five institutions of Bogotá from January 2011 to December 2017. Analyses were carried out for overall population and stratified by age group (18-59; ≥ 60 years). Results: There were 169 IPD cases; median age was 58 years, 51.5% were male, and 80.5% had at least one comorbidity. Bacteremic pneumonia was the most common presentation (63.9%). The median length of hospital stay was 12 days with high healthcare resource utilization (HCRU): 58.6% required ICU and 53.3% inotropic support. Overall case-fatality rate (CFR) was 41.4%. Clinical outcomes were worse in patients ≥60 years old with significantly higher CFR and HCRU (ICU admission, mechanical ventilation, and inotropic support) compared to those aged 18-59 years. The most frequent serotypes were 3, 6 A/C, 14, and 19A. The sensitivity to penicillin in meningitis and non-meningitis isolates were 75% and 89.1% respectively. Conclusions: IPD was associated with a substantial burden in adults and worse clinical outcomes and HCRU in older adults in Colombia. Surveillance data combined with clinical outcomes have the potential to inform age-based pneumococcal vaccination policies.

Oocyte Quality, In Vitro Fertilization and Embryo Development of Alpaca Oocytes Collected by Ultrasound-Guided Follicular Aspiration or from Slaughterhouse Ovaries.

The morphological quality and the in vitro developmental competence of cumulus-oocyte complexes (COCs) collected from in vivo or slaughtered alpacas was compared. COCs were recovered from ovarian follicles using: (i) manual aspiration in ovaries of alpacas (n = 15) sacrificed at a local slaughterhouse, or (ii) transrectal ultrasound-guided follicular aspiration (or ovum-pick-up, OPU) in live alpacas (n = 13) 4 days after the administration of an ovarian superstimulation protocol (200 UI eCG). COCs recovered from both groups were morphologically evaluated and graded. Grade I to III COCs were in vitro matured for 26 h and in vitro fertilized afterwards for 20 h using fresh alpaca epididymal spermatozoa. Presumptive zygotes from both groups were in vitro cultured for 7 days. The proportion of COCs recovered over the total number of follicles punctured was similar between groups, but the mean number of COCs collected from individual ovaries was greater (p < 0.05) in slaughterhouse ovaries. A significantly higher (p < 0.05) percentage of low-quality COCs (grades III and IV) and a lower (p < 0.05) percentage of grade I COCs was obtained using OPU. The number of blastocysts, regarding cleavage and COCs collected, was higher (p < 0.007 and p < 0.0002 respectively) for COCs collected by OPU; however, the total number of blastocysts per female did not differ between groups. We can conclude that the recovery rate and morphological quality of COCs was significantly higher when follicles were manually aspirated from slaughterhouse alpaca ovaries; however, a statistically higher developmental potential was observed in oocytes collected by OPU from live alpaca donors.

Microstructuring to Improve the Thermal Stability of GeSn Layers.

Tin segregation in Ge1-xSnx alloys is one of the major problems potentially hindering the use of this material in devices. Ge1-xSnx microdisks fabricated from layers with Sn concentrations up to 16.9% underwent here annealing at temperatures as high as 400 °C for 20 min without Sn segregation, in contrast with the full segregation observed in the corresponding blanket layers annealed simultaneously. After annealing, no changes in the elemental composition of the microdisks were evidenced. An enhancement of the total integrated photoluminescence, with no modifications of the emission energy, was also observed. These findings show that microstructuring offers a completely new path in maintaining the stability of high Sn concentration Ge1-xSnx layers at temperatures much higher than those used for growth. This approach enables the use of thermal annealing processes to improve the properties of this alloy in optoelectronic devices (such as light emitting diodes, lasers, photodetectors, or modulators). It should also facilitate the integration of Ge1-xSnx into well-established technologies requiring medium temperature processes. The same strategy may help to prevent Sn segregation during high temperature processes in similar metastable alloys.