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Unlike general anaesthesia, neuraxial anaesthesia (NA) reduces the burden and risk of respiratory adverse events in the post-operative period. However, both patients affected by chronic obstructive pulmonary disease (COPD) and chest wall disorders and/or neuromuscular diseases may experience the development or the worsening of respiratory failure, even during surgery performed under NA; this latter negatively affects the function of accessory respiratory muscles, resulting in a blunted central response to hypercapnia and possibly in an exacerbation of cardiac dysfunction (NA-induced relative hypovolemia). According to European Respiratory Society (ERS) and American Thoracic Society (ATS) guidelines, non-invasive ventilation (NIV) is effective in the post-operative period for the treatment of both impaired pulmonary gas exchange and ventilation, while the intra-operative use of NIV in association with NA is just anecdotally reported in the literature. Whilst NIV does not assure a protected patent airway and requires the patient’s cooperation, it is a handy tool during surgery under NA: NIV is reported to be successful for treatment of acute respiratory failure; it may be delivered through the patient’s home ventilator, may reverse hypoventilation induced by sedatives or inadvertent spread of anaesthetic up to cervical dermatomes, and allow the avoidance of intubation in patients affected by chronic respiratory failure, prolonging the time of non-invasiveness of respiratory support (i.e., neuromuscular patients needing surgery). All these advantages could make NIV preferable to oxygen in carefully selected patients.

We simulate the phase diagram and critical behavior of the q-state clock model on the square lattice by using the state-of-the-art loop optimization for tensor-network renormalization (loop-TNR) algorithm. The two phase transition points for q≥5 are determined with very high accuracy. Furthermore, by computing the conformal scaling dimensions for both transition points, we are able to determine the radius R of the compactified boson theories at both transition points with high precision. In particular, the radius R at higher temperature phase transition point is precisely the same as the one predicted by Berezinskii-Kosterlitz-Thouless (BKT) transition. Moreover, we find that the fixed-point tensors at higher temperature transition point also converge to the same one approximately for large enough q and the corresponding operator product expansion (OPE) coefficient of the compactified boson theory can also be read out directly from the fixed-point tensor.

SnSe single crystals have been demonstrated to possess excellent thermoelectric properties. In this work, we demonstrate a grain size control method in growing nanocrystalline SnSe thin films through a glancing angle pulsed-laser deposition approach. Structural characterization reveals that the SnSe film deposited at a normal angle has a preferred orientation along a axis, while by contrast, the SnSe film deposited at an 80° glancing angle develops a nanopillar structure with the growth direction towards the incident atomic flux. The glancing angle deposition greatly reduces the grain size of the thin film due to a shadowing effect to the adatoms, resulting in significantly increased power factor for more than 100%. The maximum Seebeck coefficient and power factor are 498.5μV/K and 18.5μWcm−1K−2, respectively. The enhancement of thermoelectric property can be attributed to the potential barrier scattering at grain boundaries owing to the reduced grain size and increased grain boundaries in the film. Given this enhanced power factor, and considering the fact that the nanopillar structure should have much lower thermal conductivity than a plain film, the zT value of such made SnSe film could be significantly larger than the corresponding single crystal film, making it a good candidate for thin film-based thermoelectric device.

Aberrant activation of the IgE receptor on mast cells leads to allergic responses. Here, the authors identify an E3 ligase and adaptor protein that can reduce IgE signalling by targeting phosphorylated-Syk for degradation.

We propose a quantum error correction protocol for continuous-variable finite-energy, approximate Gottesman-Kitaev-Preskill (GKP) states undergoing small Gaussian random displacement errors, based on the scheme of Glancy and Knill [Phys. Rev. A 73, 012325 (2006)PLRAAN1050-294710.1103/PhysRevA.73.012325]. We show that combining multiple rounds of error-syndrome extraction with Bayesian estimation offers enhanced protection of GKP-encoded qubits over comparible single-round approaches. Furthermore, we show that the expected total displacement error incurred in multiple rounds of error followed by syndrome extraction is bounded by 2sqrt[π]. By recompiling the syndrome-extraction circuits, we show that all squeezing operations can be subsumed into auxiliary state preparation, reducing them to beamsplitter transformations and quadrature measurements.

BackgroundThe efficacy of providing self-acupressure educational materials in reducing stress and improving health-related quality of life (HRQOL) is uncertain. Evidence-based data to recommend for or against self-acupressure as an intervention for reducing stress and improving HRQOL is needed.ObjectiveThe Self-Acupressure for Stress (SAS) trial evaluates whether providing self-acupressure educational materials would reduce stress and improve HRQOL among health care providers (HCPs).DesignRandomized behavioral clinical trial.SettingThe entire study took place remotely.ParticipantsOne hundred fifty-nine adult HCPs with no prior experience or training in acupressure.InterventionThe intervention group received self-acupressure educational materials.MeasurementsPrimary outcomes were perception of stress measured by the Perceived Stress Scale (PSS), as well as scores on the physical and mental components of the 12-item Short Form Health Survey version 2 (SF-12v2).ResultsFrom the baseline to midpoint evaluations, the intervention group significantly reduced their PSS score (P ≤ .001) and increased their SF-12v2 Mental score (P = .002) but not their SF-12v2 Physical score (P = .55). These findings persisted at the final follow-up (both PSS and SF-12v2 Mental changes from baseline P < .001). However the control group also significantly improved their SF-12v2 Mental from baseline to midpoint (P = .01) which was maintained at final follow-up (P = .02), whereas PSS and SF-12v2 Physical did not significantly change from baseline at either mid or final. Finally, the intervention group improved by significantly more than the control group from baseline to final follow-up for both PSS (P = .007) and SF-12v2 Mental (P = .02) HRQOL measures.LimitationThe trial was not blinded.ConclusionAmong HCPs during the coronavirus disease 2019 (COVID-19) pandemic, the provision of self-acupressure educational materials safely improved self-reported assessments of perception of stress and mental health. Self-acupressure represents a promising intervention for other populations. The study findings support the use of self-acupressure to reduce stress and improve HRQOL.Trial registrationClinicalTrials.gov: NCT04472559.

Psychiatric illnesses, such as schizophrenia, are most likely caused by an interaction between genetic predisposition and environmental factors, including stress during development. The neurotrophin, brain-derived neurotrophic factor (BDNF) has been implicated in this illness as BDNF levels are decreased in the brain of patients with schizophrenia. The aim of the present study was to assess the combined effect of reduced BDNF levels and postnatal stress, simulated by chronic young-adult treatment with the stress hormone, corticosterone. From 6 weeks of age, female and male BDNF heterozygous mice and their wild-type controls were chronically treated with corticosterone in their drinking water for 3 weeks. At 11 weeks of age, male, but not female BDNF heterozygous mice treated with corticosterone exhibited a profound memory deficit in the Y-maze. There were no differences between the groups in baseline prepulse inhibition (PPI), a measure of sensorimotor gating, or its disruption by treatment with MK-801. However, an increase in startle caused by MK-801 treatment was absent in male, but not female BDNF heterozygous mice, irrespective of corticosterone treatment. Analysis of protein levels of the NMDA receptor subunits NR1, NR2A, NR2B and NR2C, showed a marked increase of NR2B levels in the dorsal hippocampus of male BDNF heterozygous mice treated with corticosterone. In the ventral hippocampus, significantly reduced levels of NR2A, NR2B and NR2C were observed in male BDNF heterozygous mice. The NMDA receptor effects in hippocampal sub-regions could be related to the spatial memory deficits and the loss of the effect of MK-801 on startle in these mice, respectively. No significant changes in NMDA receptor subunit levels were observed in any of the female groups. Similarly, no significant changes in levels of BDNF or its receptor, TrkB, were found other than the expected reduced levels of BDNF in heterozygous mice. In conclusion, the data show differential interactive effects of reduced levels of BDNF expression and corticosterone treatment on spatial memory and startle in male and female mice, accompanied by significant, but region-specific changes in NMDA receptor subunit levels in the dorsal and ventral hippocampus. These results could be important for our understanding of the interaction of neurodevelopmental stress and BDNF deficiency in cognitive and anxiety-related symptoms of psychiatric illnesses, such as schizophrenia.

Lead-free thermoelectric material, copper chalcogenides, have been attracting much interest from many research and industrial applications owing to their high capability of harvesting energy from heat. The state-of-the-art copper chalcogenides are commonly fabricated by the spark plasma sintering (SPS) and hot pressing (HP) techniques. Those methods are still costly and complicated particularly when compared to the conventional solid-state sintering method. Here, we report an easy-to-fabricate lead-free copper(I)-selenium (Cu2Se) that was fabricated using the conventional sintering method. The fabrication conditions, including sintering temperature and dwelling time, have been systematically studied to optimize the thermoelectric performance of Cu2Se. The optimized zT value for the pure Cu2Se was found to be 1.2 for the sample sintered at 1173 K for 2 h. The study shows that Cu2Se developed using the simple and low-cost techniques could exhibit comparable thermoelectric performance when compared with those fabricated by the SPS method, which provides an alternative potential technique to synthesize high-performance thermoelectric materials in a cost-effective way for industrialization.

Shark conservation has become a focus of current international conservation efforts. However, the misunderstanding of sharks and their negative public portrayal may hinder their conservation. More importantly, the consumption of shark fin, which is very common in Chinese cultures, poses a significant threat to sharks. Hong Kong has long been the world's largest shark fin trading center. Shark conservation would become more sustainable if public understanding of this predatory fish and an appreciation of its ecological significance could be promoted. It is possible that the demand for fins could be effectively managed through long-term educational efforts targeted at younger generations. To provide essential baseline data for planning of these educational efforts, this project investigated the perceptions of 11 to 12 year-old primary school students in Hong Kong about sharks, and their understanding of ecological concepts and shark-related knowledge. The findings indicate that these students lack sufficient knowledge and possess misconceptions about sharks and their ecological significance in the marine ecosystem. The students' conceptual understanding level is strongly correlated with their perceptions. Correlational analyses further demonstrated a positive association between formal education and perceptions toward shark conservation. The students who favoured shark fin consumption did so because of its tastiness, whereas concerns about shark population decline and the cruelty of shark hunting were the main reasons for not favoring shark fin consumption. This pilot study provides preliminary but important insights into primary school education regarding the conservation of sharks.

Justificación: El cáncer de cérvix es la patología neoplásica más frecuente entre la población femenina. En casos de invasión localizada, la histerectomía radical puede considerarse un tratamiento curativo, sin embargo, el sangrado transoperatorio significativo hace necesaria la transfusión en muchos casos, con todas las complicaciones que esta conlleva. Hasta donde sabemos, no hay ningún estudio publicado en la bibliografía nacional, acerca de la técnica de hemodilución isovolémica para reducir los requerimientos transfusionales en estas pacientes. Objetivos: a) Hacer experiencia clínica con la Hemodilución isovolémica en pacientes sometidas a histerectomía radical por cáncer de cérvix; b) Evaluar la utilidad de la Hemodilución isovolémica como un método para reducir la necesidad de transfusión de sangre alogénica. Materiales y métodos: El estudio fue prospectivo. Se seleccionó en forma consecutiva a todas las pacientes sometidas a histerectomía radical por cáncer de cérvix, del Servicio de Ginecología Oncológica del Hospital Dr. Rafael Ángel Calderón Guardia, entre los meses de enero de 2000 a enero de 2001. Se realizó sangría, a través de una línea arterial, un volumen hemático calculado con base en el peso y el hematocrito de la paciente. La sangre autóloga fue retransfundida al término de la cirugía. Resultados: Un total de 12 pacientes fueron incluidas en el estudio. La edad promedio fue de 55,5 + 10,4 años. La mayoría tuvo el cáncer de cérvix en estadío I-B1 (n = 10), el resto, en el estadío I-B2 (n = 1) y I-A2 (n = 1). Se obtuvo un promedio de 1208 ml de sangre autóloga por paciente. El procedimiento fue bien tolerado, excepto en una, quien presentó compromiso hemodinámico atribuible a la sangría. Al comparar los valores basales con los obtenidos antes de la retransfusión, se observó un descenso promedio de la hemoglobina, hematocrito y plaquetas de 4,2 g/dl, un 14,4% y 52.000 μl, respectivamente. Ninguna de las pacientes ameritσ transfusiσn de sangre alogιnica. Conclusiones: La hemodilución isovolémica preoperatoria es una técnica sencilla y eficaz para reducir la necesidad de transfusión de sangre alogénica en pacientes sometidas a histerectomía radical por cáncer de cérvix. Se asocia con una baja incidencia de complicaciones, pero es recomendable la vigilancia estrecha del estado hemodinámico transoperatorio, en especial durante el momento de la sangría.

The development of the thermoelectric (TE) power generation is rapid, and the applications have extensively been studied. The principle is based on the Seebeck effect, in which the temperature difference between hot and cold sides of the TE material converts to electrical energy. In this paper, a design is proposed to convert the thermal energy between indoor and outdoor of a board to electrical energy by the thermoelectric generator (TEG). Furthermore, the electrical energy generated is charged to supercapacitors as a battery or a power supply to the loads (e.g., lights) of the house. Besides the experimental work, a thermal model and an electrical model of the TEG have been proposed. To study the power generation performance in terms of materials, the simulation of the conversion efficiency of the TE board using materials with different thermal conductance have also been conducted. It was found that, using graphene as the thermally conductive material, the conversion efficiency was enhanced by 1.6% and 1.7%, when the temperature difference was 15 °C and 40 °C, respectively.

Justificación: La oclusión trombótica de las venas cerebrales o senos durales es una causa menos frecuente de enfermedad cerebrovascular que la trombosis arterial. Sin embargo; los estudios epidemiológicos indican que esta entidad no es tan inusual como o ser pensaba previamente. Hasta donde sabemos, no hay ningún estudio publicando al respecto en la literatura nacional, siendo precisamente el motivo del presente trabajo. Objetivos: Identificar las características demográficas, clínicas y diagnósticas de los pacientes que sufrieron una trombosis de senos venosos durales. Describir los métodos terapéuticos empleados y la evolución que tuvieron estos pacientes. Materiales y métodos: Se revisaron los expedientes clínicos de 11 casos diagnosticados de trombosis de senos durales en el Hospital Dr. Rafael Ángel Calderón Guardia, en el período comprendido entre enero de 1996 a enero de 1999. Se analizaron los posibles factores de riego, formas de presentación clínica, estudios de radio imagen y tratamiento empleado. Resultados: El promedio de edad fue de 32,6 años. Un 18,2% fueron varones, mientras que el 81,8% correspondió a mujeres. Las manifestaciones más frecuentes fueron: cefalea (100%), vómito (91%), déficit motor 882%), alteración del sensorio (73%), papiledema (54,5%), crisis convulsiva (54,5%) y datos de irritación meníngea (36,4%): el signo del delta vacío se documentó en 27,3% de los estudios tomográficos. El seno sagital superior fue el más frecuentemente afectado (91%). Se anticoaguló con heparina intravenosa al 54, 5% de los casos. Conclusiones: Aunque somos conscientes de las limitaciones de nuestra serie, nuestra intención ha sido llamar la atención sobre una patología vascular cerebral, que aunque no es tan frecuente como su contraparte arterial, debe tenerse en consideración por sus potenciales efectos sobre la salud del paciente. El conocimiento adecuado de esta condición es importante, debido a que aún cuando los síntomas son severos, la reversibilidad puede ser completa.

El taponamiento pericárdico es una entidad de creciente incidencia, debido principalmente al incremento en los traumatismos cardiotorácicos y procedimientos invasivos. Fisiopatológicamente, se caracteriza por ser una condición en la que se limita la expansión de las cámaras cardíacas, como consecuencia de la compresión aguda de ellas por aumento del volumen y de la presión del líquido pericárdico. Este estado puede evolucionar hacia un shock obstructivo potencialmente letal si no es diagnosticado y tratado oportunamente.The incidence of cardiac tamponade is increasing. This is mainly due to cardiothoracic trauma and invasive procedures. From the pathophysiological point of view, it is characterized by a restriction to the expansion of the cardiac chambers as a consequence of increased intrapericardial pressure and volume. This state can change lo a obstructive shock which is potentially lethal if not promptly diagnosed and treated.

Botulinum neurotoxins (BoNTs) are among the most lethal toxins known to humans, comprising seven established serotypes termed BoNT/A-G encoded in two types of gene clusters (ha and orfX) in BoNT-producing clostridia. The ha cluster encodes four non-toxic neurotoxin-associated proteins (NAPs) that assemble with BoNTs to protect and enhance their oral toxicity. However, the structure and function of the orfX-type NAPs remain largely unknown. Here, we report the crystal structures for OrfX1, OrfX2, and an OrfX1-OrfX3 complex, which are encoded in the orfX cluster of a BoNT/E1-producing Clostridium botulinum strain associated with human foodborne botulism. These structures lay the foundation for future studies on the potential roles of OrfX proteins in oral intoxication and pathogenesis of BoNTs.

Botulinum neurotoxin E (BoNT/E) is one of the major causes of human botulism and paradoxically also a promising therapeutic agent. Here we determined the co-crystal structures of the receptor-binding domain of BoNT/E (HCE) in complex with its neuronal receptor synaptic vesicle glycoprotein 2A (SV2A) and a nanobody that serves as a ganglioside surrogate. These structures reveal that the protein-protein interactions between HCE and SV2 provide the crucial location and specificity information for HCE to recognize SV2A and SV2B, but not the closely related SV2C. At the same time, HCE exploits a separated sialic acid-binding pocket to mediate recognition of an N-glycan of SV2. Structure-based mutagenesis and functional studies demonstrate that both the protein-protein and protein-glycan associations are essential for SV2A-mediated cell entry of BoNT/E and for its potent neurotoxicity. Our studies establish the structural basis to understand the receptor-specificity of BoNT/E and to engineer BoNT/E variants for new clinical applications.

Mast cells are pivotal in the pathogenesis of allergy and inflammation. In addition to the classical IgE-dependent mechanism involving crosslinking of the high-affinity receptor for IgE (FcεRI), mast cells are also activated by Toll-like receptors (TLRs) which are at the center of innate immunity. In this study, we demonstrated that the response of LAD2 cells (a human mast cell line) to anti-IgE was altered in the presence of the TLR2 agonists peptidoglycan (PGN) and tripalmitoyl-S-glycero-Cys-(Lys)4 (Pam3CSK4). Pretreatment of PGN and Pam3CSK4 inhibited anti-IgE induced calcium mobilization and degranulation without down-regulation of FcεRI expression. Pam3CSK4 but not PGN acted in synergy with anti-IgE for IL-8 release when the TLR2 agonist was added simultaneously with anti-IgE. Studies with inhibitors of key enzymes implicated in mast cell signaling revealed that the synergistic release of IL-8 induced by Pam3CSK4 and anti-IgE involved ERK and calcineurin signaling cascades. The differential modulations of anti-IgE induced mast cell activation by PGN and Pam3CSK4 suggest that dimerization of TLR2 with TLR1 or TLR6 produced different modulating actions on FcεRI mediated human mast cell activation.

BACKGROUND: Decompressive craniectomy has been traditionally used as a lifesaving rescue treatment in severe traumatic brain injury (TBI). This study assessed whether objective information on long-term prognosis would influence healthcare workers' opinion about using decompressive craniectomy as a lifesaving procedure for patients with severe TBI. METHOD: A two-part structured interview was used to assess the participants' opinion to perform decompressive craniectomy for three patients who had very severe TBI. Their opinion was assessed before and after knowing the predicted and observed risks of an unfavourable long-term neurological outcome in various scenarios. RESULTS: Five hundred healthcare workers with a wide variety of clinical backgrounds participated. The participants were significantly more likely to recommend decompressive craniectomy for their patients than for themselves (mean difference in visual analogue scale [VAS] -1.5, 95% confidence interval -1.3 to -1.6), especially when the next of kin of the patients requested intervention. Patients' preferences were more similar to patients who had advance directives. The participants' preferences to perform the procedure for themselves and their patients both significantly reduced after knowing the predicted risks of unfavourable outcomes, and the changes in attitude were consistent across different specialties, amount of experience in caring for similar patients, religious backgrounds, and positions in the specialty of the participants. CONCLUSIONS: Access to objective information on risk of an unfavourable long-term outcome influenced healthcare workers' decision to recommend decompressive craniectomy, considered as a lifesaving procedure, for patients with very severe TBI.

Botulinum neurotoxins (BoNTs) are among the deadliest of bacterial toxins. BoNT serotype A and B in particular pose the most serious threat to humans because of their high potency and persistence. To date, there is no effective treatment for late post-exposure therapy of botulism patients. Here, we aim to develop single-domain variable heavy-chain (VHH) antibodies targeting the protease domains (also known as the light chain, LC) of BoNT/A and BoNT/B as antidotes for post-intoxication treatments. Using a combination of X-ray crystallography and biochemical assays, we investigated the structures and inhibition mechanisms of a dozen unique VHHs that recognize four and three non-overlapping epitopes on the LC of BoNT/A and BoNT/B, respectively. We show that the VHHs that inhibit the LC activity occupy the extended substrate-recognition exosites or the cleavage pocket of LC/A or LC/B and thus block substrate binding. Notably, we identified several VHHs that recognize highly conserved epitopes across BoNT/A or BoNT/B subtypes, suggesting that these VHHs exhibit broad subtype efficacy. Further, we identify two novel conformations of the full-length LC/A, that could aid future development of inhibitors against BoNT/A. Our studies lay the foundation for structure-based engineering of protein- or peptide-based BoNT inhibitors with enhanced potencies and cross-subtypes properties.