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In Colombia, cancer is recognized as a high-cost pathology by the national government and the Colombian High-Cost Disease Fund. As of 2020, the situation is most critical for adult cancer patients, particularly those under public healthcare and residing in remote regions of the country. The highest lag time for a diagnosis was observed for cervical cancer (79.13 days), followed by prostate (77.30 days), and breast cancer (70.25 days). Timely and accurate histopathological reporting plays a vital role in the diagnosis of cancer. In recent years, digital pathology has been globally implemented as a technological tool in two main areas: telepathology (TP) and computational pathology. TP has been shown to improve rapid and timely diagnosis in anatomic pathology by facilitating interaction between general laboratories and specialized pathologists worldwide through information and telecommunication technologies. Computational pathology provides diagnostic and prognostic assistance based on histopathological patterns, molecular, and clinical information, aiding pathologists in making more accurate diagnoses. We present the study protocol of the GLORIA digital pathology network, a pioneering initiative, and national grant-approved program aiming to design and pilot a Colombian digital pathology transformation focused on TP and computational pathology, in response to the general needs of pathology laboratories for diagnosing complex malignant tumors. The study protocol describes the design of a TP network to expand oncopathology services across all Colombian regions. It also describes an artificial intelligence proposal for lung cancer, one of Colombia's most prevalent cancers, and a freely accessible national histopathological image database to facilitate image analysis studies.

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Medicine is a discipline based on and nurtured by scientific research and technological development. The use of health services supported by information technology is increasing worldwide, and Latin America is no exception. Factors such as needing more specialists in peripheral cities, large geographic areas, and socio-cultural aspects limit the possibility of receiving timely and quality medical care services. Information Technology (IT) for health purposes, such as e-health, is a cost-effective solution for equitable access to quality healthcare services and optimization of the rising associated costs. As an e-health service, telemedicine facilitates and mediates distance communication between the patient and medical staff. Even though Latin America is at the beginning of the development of telemedicine, it would have a relevant impact, given the geographic and socioeconomic conditions of the population in this part of the world. Drawing on the extended Unified Theory of Acceptance and Use of Technology (UTAUT2) theory, we developed a theoretical model to identify the latent factors influencing the public acceptance of telemedicine and examined their interrelationships. A survey questionnaire was designed and administered to 391 residents in Antofagasta, a mine region of Chile. After that, structural equation modeling was employed to analyze the survey data. The results reveal that the UTAUT2 factors' performance expectancy, social influence, and price value significantly impact the intention to use (R2 = 0.693). Additionally, the model presented a good fit. This study enriches the existing theoretical research on the acceptance of telemedicine services and offers insights into understanding and managing technology in the Chilean health sector.

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Photoacoustic (PA) imaging has the potential to deliver non-invasive diagnostic information. However, skin tone differences bias PA target visualization, as the elevated optical absorption of melanated skin decreases optical fluence within the imaging plane and increases the presence of acoustic clutter. This paper demonstrates that short-lag spatial coherence (SLSC) beamforming mitigates this bias. PA data from the forearm of 18 volunteers were acquired with 750-, 810-, and 870-nm wavelengths. Skin tones ranging from light to dark were objectively quantified using the individual typology angle (ITA°). The signal-to-noise ratio (SNR) of the radial artery (RA) and surrounding clutter were measured. Clutter was minimal (e.g., -16 dB relative to the RA) with lighter skin tones and increased to -8 dB with darker tones, which compromised RA visualization in conventional PA images. SLSC beamforming achieved a median SNR improvement of 3.8 dB, resulting in better RA visualization for all skin tones.

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In the present work, the impact that the longitudinal shape of channels has on the current produced in the flow of a magneto-hydrodynamic microgenerator (MHDMG) is studied. The goal is to find the micro-channel geometry via modeling to maximize the current output for low Reynolds and Mach regimes. To carry out this study, a 3D dynamic numerical tool relying on the finite volume method was handled with the open-source software OpenFOAM. It is the base model to study the impact of intricate geometries on the ability to produce energy. An additional steady-state 2D analytical model was also developed to check some basic modeling assumptions. Both models have been experimentally validated on the simplest flow system having a constant square cross-section throughout. The results produced by both models cross-check very well and compare favorably with respect to experimental data. Hence, using the validated numerical tool, three shapes have been further investigated, namely, progressive (linear decrease of the cross-section), arc (parabolic decrease of the cross-section), and wavy (sinusoidal shape). It was found that the arc channel provides the greatest current output for the same volumetric flow. It is therefore the preferred choice for developing high current gain and more efficient MHDMG used in micro-scaled actuators and sensors.

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Cebus monkeys stand out from other New World monkeys by their ability to perform fine hand movements, and by their spontaneous use of tools in the wild. Those behaviors rely on the integration of somatosensory information, which occurs in different areas of the parietal cortex. Although a few studies have examined and parceled the somatosensory areas of the cebus monkey, mainly using electrophysiological criteria, very little is known about its anatomical organization. In this study we used SMI-32 immunohistochemistry, myelin, and Nissl stains to characterize the architecture of the parietal cortical areas of cebus monkeys. Seven cortical areas were identified between the precentral gyrus and the anterior bank of the intraparietal sulcus. Except for areas 3a and 3b, distinction between different somatosensory areas was more evident in myelin-stained sections and SMI-32 immunohistochemistry than in Nissl stain, especially for area 2 and subdivisions of area 5. Our results show that cebus monkeys have a relatively complex somatosensory cortex, similar to that of macaques and humans. This suggests that, during primate evolution, the emergence of new somatosensory areas underpinned complex manual behaviors in most Old World simians and in the New World cebus monkey. J. Comp. Neurol. 524:1399-1423, 2016. © 2015 Wiley Periodicals, Inc.

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The optic tectum in birds and its homologue the superior colliculus in mammals both send major bilateral, nontopographic projections to the nucleus rotundus and caudal pulvinar, respectively. These projections originate from widefield tectal ganglion cells (TGCs) located in layer 13 in the avian tectum and in the lower superficial layers in the mammalian colliculus. The TGCs characteristically have monostratified arrays of brush-like dendritic terminations and respond mostly to bidimensional motion or looming features. In birds, this TGC-mediated tectofugal output is controlled by feedback signals from the nucleus isthmi pars parvocellularis (Ipc). The Ipc neurons display topographically organized axons that densely ramify in restricted columnar terminal fields overlapping various neural elements that could mediate this tectofugal control, including the retinal terminals and the TGC dendrites themselves. Whether the Ipc axons make synaptic contact with these or other tectal neural elements remains undetermined. We double labeled Ipc axons and their presumptive postsynaptic targets in the tectum of chickens (Gallus gallus) with neural tracers and performed an ultrastructural analysis. We found that the Ipc terminal boutons form glomerulus-like structures in the superficial and intermediate tectal layers, establishing asymmetric synapses with several dendritic profiles. In these glomeruli, at least two of the postsynaptic dendrites originated from TGCs. We also found synaptic contacts between retinal terminals and TGC dendrites. These findings suggest that, in birds, Ipc axons control the ascending tectal outflow of retinal signals through direct synaptic contacts with the TGCs.

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Retinal inputs to the optic tectum (TeO) triggered by moving stimuli elicit synchronized feedback signals from two isthmic nuclei: the isthmi parvocelullaris (Ipc) and isthmi semilunaris (SLu). Both of these nuclei send columnar axon terminals back to the same tectal position receiving the retinal input. The feedback signals from the Ipc seem to act as an attentional spotlight by selectively boosting the propagation of retinal inputs from the tectum to higher visual areas. Although Ipc and SLu nuclei are widely considered cholinergic because of their immunoreactivity for choline acetyltransferase (ChAT), contradictory findings, including the expression of the vesicular glutamate transporter 2 (VGluT2) mRNA in Ipc neurons, have raised doubts about the purely cholinergic nature of this nucleus. In this study, in chicks, we revise the neurochemical identity of the isthmic nuclei by using in situ hybridization assays for VGluT2 along with three cholinergic markers: the vesicular acetylcholine transporter (VAChT), the high-affinity choline transporter (CHT1) and ChAT. We found that neurons in the SLu showed strong mRNA expression of all three cholinergic markers, whereas the expression of VAChT mRNA in the Ipc was undetectable in our essays. Instead, Ipc neurons exhibited a strong expression of VGluT2 mRNA. Immunohistochemistry assays showed VGluT2 immunoreactivity in the TeO codistributing with anterogradely labeled Ipc axon-terminal boutons, further supporting a glutamatergic function for the Ipc nucleus. Therefore, our results strongly suggest that, in the chick, whereas the feedback from the SLu to the TeO is indeed cholinergic, the feedback from the Ipc has a marked glutamatergic component.

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Among social insects, the stingless bees (Apidae, Meliponini), a mainly tropical group of highly eusocial bees, present an intriguing variety of well-described olfactory-dependent behaviors showing both caste- and sex-specific adaptations. By contrast, little is known about the neural structures underlying such behavioral richness or the olfactory detection and processing abilities of this insect group. This study therefore aimed to provide the first detailed description and comparison of the brains and primary olfactory centers, the antennal lobes, of the different members of a colony of the stingless bee Melipona scutellaris. Global neutral red staining, confocal laser scanning microscopy, and 3D reconstructions were used to compare the brain structures of males, workers, and virgin queens with a special emphasis on the antennal lobe. We found significant differences between both sexes and castes with regard to the relative volumes of olfactory and visual neuropils in the brain and also in the number and volume of the olfactory glomeruli. In addition, we identified one (workers, queens) and three or four (males) macroglomeruli in the antennal lobe. In both sexes and all castes, the largest glomerulus (G1) was located at a similar position relative to four identified landmark glomeruli, close to the entrance of the antennal nerve. This similarity in position suggests that G1s of workers, virgin queens, and males of M. scutellaris may correspond to the same glomerular entity, possibly tuned to queen-emitted volatiles since all colony members need this information.

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Two new charged particle detectors have been flown in five recent Shuttle flights. The tissue-equivalent proportional counter measures the lineal energy spectrum of space radiation in the 0.26-300 keV micrometer-1 range. The charged particle spectrometer is a double dE/dx x E and dE/dx x Chrenekov detector system which provides a measurement of the differential energy spectrum of protons from 13 to 350 MeV and dose rate in silicon. In this paper the dose rate, equivalent dose rate, and radiation, quality factor for trapped protons and cosmic radiation are reported on separately. A comparison of the integral LET spectra with recent transport code calculations shows significant disagreement. Using the calculated dose rate from the omnidirectional AP8MAX model with IGRF reference magnetic field epoch 1970, and observed dose rate as a function of geographic latitude and longitude, the westward drift of the south Atlantic anomaly has been determined. The east-west effect has also been studied and a 'second' radiation belt observed. A comparison of the galactic cosmic radiation (GCR) lineal energy transfer spectra with model calculations shows disagreement comparable with those of the trapped protons.

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Increasingly, there is a need in both research and clinical practice to document and quantify sleep and waking behaviors in a comprehensive manner. The Pittsburgh Sleep Diary (PghSD) is an instrument with separate components to be completed at bedtime and waketime. Bedtime components relate to the events of the day preceding the sleep, waketime components to the sleep period just completed. Two-week PghSD data is presented from 234 different subjects, comprising 96 healthy young middle-aged controls, 37 older men, 44 older women, 29 young adult controls and 28 sleep disorders patients in order to demonstrate the usefulness, validity and reliability of various measures from the instrument. Comparisons are made with polysomnographic and actigraphic sleep measures, as well as personality and circadian type questionnaires. The instrument was shown to have sensitivity in detecting differences due to weekends, age, gender, personality and circadian type, and validity in agreeing with actigraphic estimates of sleep timing and quality. Over a 12-31 month delay, PghSD measures of both sleep timing and sleep quality showed correlations between 0.56 and 0.81 (n = 39, P < 0.001).

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To measure the radiation environment in the Spacelab (SL) module and on the pallet, a set of passive and active radiation detectors was flown as part of the Verification Flight Instrumentation (VFI). SL 1 carried 4 passive and 2 active detector packages which, with the data from the 26 passive detectors of Experiment INS006, provided a comprehensive survey of the radiation environment within the spacecraft. SL 2 carried 2 passive VFI units on the pallet. Thermoluminescent dosimeters (TLDs) measured the low linear energy transfer (LET) dose component; the HZE fluence and LET spectra were mapped with CR-39 track detectors; thermal and epithermal neutrons were measured with the use of fission foils; metal samples analyzed by gamma ray spectroscopy measured low levels of several activation lines. The TLDs registered from 97 to 143 mrad in the SL 1 module. Dose equivalents of 330 +/- 70 mrem in the SL 1 module and 537 +/- 37 mrem on the SL 2 pallet were measured. The active units in the SL 1 module each contained an integrating tissue-equivalent ion chamber and two differently-shielded xenon-filled proportional counters. The ion chambers accumulated 125 and 128 mrads for the mission with 17 and 12 mrads accumulated during passages through the South Atlantic Anomaly (SAA). The proportional counter rates (approximately 1 cps at sea level) were approximately 100 cps in the middle of the SAA (mostly protons), approximately 35 cps at large geomagnetic latitudes (cosmic rays) and approximately 100 cps in the South Horn of the electron belts (mostly bremsstrahlung). Detailed results of the measurements and comparison with calculated values are described.

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