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1.
Nanophotonics ; 13(14): 2531-2540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38836103

RESUMO

The short exciton diffusion length in organic semiconductors results in a strong dependence of the conversion efficiency of organic photovoltaic (OPV) cells on the morphology of the donor-acceptor bulk-heterojunction blend. Strong light-matter coupling provides a way to circumvent this dependence by combining the favorable properties of light and matter via the formation of hybrid exciton-polaritons. By strongly coupling excitons in P3HT-C60 OPV cells to Fabry-Perot optical cavity modes, exciton-polaritons are formed with increased propagation lengths. We exploit these exciton-polaritons to enhance the internal quantum efficiency of the cells, determined from the external quantum efficiency and the absorptance. Additionally, we find a consistent decrease in the Urbach energy for the strongly coupled cells, which indicates the reduction of energetic disorder due to the delocalization of exciton-polaritons in the optical cavity.

2.
Ultrason Sonochem ; 108: 106966, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38924854

RESUMO

In recent years, researchers have increasingly focused on the development of multiphase trimetallic nanocomposites (TMNC) incorporating ternary metals or metal oxides, which hold significant potential as alternatives for combatting biofilms and bacterial infections. Enhanced oral health is ensured by the innovative techniques used to effectively prevent bacterial adherence and formation of biofilm on dental sutures. In this investigation, TMNC, which consists of Pb, Ag, and Cu, was synthesized using an autoclave-assisted sonochemical technique. Following synthesis, TMNC were characterized using FTIR, XRD, BET, XPS, TGA, and Raman spectroscopy to analyze their shape and microstructure. Subsequent evaluations, including MTT assay, antibacterial activity testing, and biofilm formation analysis, were conducted to assess the efficiency of the synthesized TMNC. Cytotoxicity and anti-human oral squamous cell carcinoma activities of TMNC were evaluated using the Human Oral Cancer cell line (KB) cell line through MTT assay, demonstrating a dose-dependent increase in anti-human oral squamous cell carcinoma activity against the KB cell line compared to the normal cell line, resulting in notably high cell viability. Furthermore, an ultrasonic probe was employed to incorporate TMNC onto dental suturing threads, with different concentrations of TMNC, ultrasonic power levels, and durations considered to determine optimal embedding conditions that result in the highest antibacterial activity. The inhibitory effects of TMNC, both in well diffusion assays and when incorporated into dental suturing threads, against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria on Mueller-Hinton agar (MHA) were assessed using various concentrations of TMNC. The results of the study indicated that the efficacy of TMNC in inhibiting bacterial growth on dental suturing threads remained impressive, even at low concentrations. Moreover, an evaluation of their potential to destabilize biofilms formed by S. aureus and E. coli, the two pathogens in humans, indicated that TMNC would be a promising anti-biofilm agent.


Assuntos
Antibacterianos , Biofilmes , Cobre , Chumbo , Nanocompostos , Prata , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanocompostos/química , Cobre/química , Cobre/farmacologia , Prata/química , Prata/farmacologia , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Chumbo/química , Ondas Ultrassônicas , Odontologia , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Staphylococcus aureus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Escherichia coli/efeitos dos fármacos
3.
Khirurgiia (Mosk) ; (6): 28-35, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38888016

RESUMO

OBJECTIVE: To demonstrate clinical features and outcomes in patients with cavitary lung lesions and COVID-19 associated pneumonia. MATERIAL AND METHODS: A retrospective analysis of electronic medical records of 8261 patients with COVID-19 was performed. We selected 40 patients meeting the inclusion criteria. Sex, age, hospital-stay, lung tissue lesion, comorbidities, treatment, methods of respiratory support, complications and outcomes were evaluated. RESULTS: Cavitary lung lesions were more common in men (67.5%). Age of patients ranged from 28 to 88 (mean 64.9±13.7) years. Hospital-stay in patients with cavitary lung lesions was 9-58 (median 27.5) days. There were 18 complications in 14 (35%) patients. Pneumothorax, isolated pneumomediastinum, pleural empyema, hemoptysis and sigmoid colon perforation were considered as complications of cavitary lung lesions. Nine (22.5%) patients died (5 of them with complications). Three patients died after surgical treatment. Long-term results were analyzed in 8 (25.8%) patients. Patients were followed-up for 3 months after discharge. Shrinkage of lesions occurred after 7-60 (mean 23) days, and complete obliteration of cavities came after 32 (range 14-90) days. CONCLUSION: Cavitary lung lesions are a rare complication of COVID-19 pneumonia. There was no significant correlation of complications with age, sex, therapy, volume of lung lesions and non-invasive ventilation (NIV). Despite more common fatal outcomes in older patients undergoing NIV, the last one was prescribed exclusively due to disease progression and respiratory failure. Further research on this problem is necessary to identify possible risk factors of cavitary lung lesions.


Assuntos
COVID-19 , Humanos , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , SARS-CoV-2 , Pulmão/diagnóstico por imagem , Adulto , Tempo de Internação/estatística & dados numéricos
4.
Annu Rev Phys Chem ; 75(1): 509-534, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38941525

RESUMO

The ability of nanophotonic cavities to confine and store light to nanoscale dimensions has important implications for enhancing molecular, excitonic, phononic, and plasmonic optical responses. Spectroscopic signatures of processes that are ordinarily exceedingly weak such as pure absorption and Raman scattering have been brought to the single-particle limit of detection, while new emergent polaritonic states of optical matter have been realized through coupling material and photonic cavity degrees of freedom across a wide range of experimentally accessible interaction strengths. In this review, we discuss both optical and electron beam spectroscopies of cavity-coupled material systems in weak, strong, and ultrastrong coupling regimes, providing a theoretical basis for understanding the physics inherent to each while highlighting recent experimental advances and exciting future directions.

5.
J Colloid Interface Sci ; 671: 145-153, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38795535

RESUMO

Wood-derived carbon, with its strong tracheid array structure, is an ideal material for use as a self-supporting electrode in supercapacitors. By leveraging the inherent through pore structure and surface affinity found in wood tracheids, we successfully engineered a highly spatially efficient cube-templated porous carbon framework inside carbonized wood tracheid cavities through precise control over precursor crystallization temperatures. This innovative cubic channel architecture effectively maximizes up to (79 ± 1)% of the cavity volume in wood-derived carbon while demonstrating exceptional hydrophilicity and high conductivity properties, facilitating the development of supercapacitors with enhanced areal/volumetric capacitances (2.65F cm-2/53.0F cm-3 at 5.0 mA cm-2) as well as superior areal/volumetric energy densities (0.37 mWh cm-2/7.36 mWh cm-3 at 2.5 mW cm-2). The fabrication of these cube-templated channels with high cube filling content is not only simple and precisely controllable, but also environmentally friendly. The proposed method eliminates the conventional acid-base treatment process for pore formation, facilitating the rapid development and practical implementation of thick electrodes with superior performance in supercapacitors. Moreover, it offers a universal research approach for the commercialization of wood-derived thick electrodes.

6.
Open Res Eur ; 4: 17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764756

RESUMO

The changes in the energy sector after the Paris agreement and the establishment of the Green Deal, pressed the governments to embrace new measures to reduce greenhouse gas emissions. Among them, is the replacement of fossil fuels by renewable energy sources or carbon-neutral alternative means, such as green hydrogen. As the European Commission approved green hydrogen as a clean fuel, the interest in investments and dedicated action plans related to its production and storage has significantly increased. Hydrogen storage is feasible in aboveground infrastructures as well as in underground constructions. Proper geological environments for underground hydrogen storage are porous media and rock cavities. Porous media are classified into depleted hydrocarbon reservoirs and aquifers, while rock cavities are subdivided into hard rock caverns, salt caverns, and abandoned mines. Depending on the storage option, various technological requirements are mandatory, influencing the required capital cost. Although the selection of the optimum storage technology is site depending, the techno-economical appraisal of the available underground storage options featured the porous media as the most economically attractive option. Depleted hydrocarbon reservoirs were of high interest as site characterisation and cavern mining are omitted due to pre-existing infrastructure, followed by aquifers, where hydrogen storage requires a much simpler construction. Research on data analytics and machine learning tools will open avenues for consolidated knowledge of geological storage technologies.

7.
Khirurgiia (Mosk) ; (5): 36-42, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38785237

RESUMO

OBJECTIVE: To identify the risk factors of pulmonary cavitation in COVID-19 pneumonia. MATERIAL AND METHODS: A retrospective study included 8261 patients with COVID-19 between April 2020 and March 2022. Inclusion criteria: age >18 years, COVID-19 confirmed by polymerase chain reaction. Two cohorts of patients were formed: 40 patients with pulmonary cavitation and 40 patients without these lesions. Both groups were comparable in age, lung lesion volume and oxygenation. Sex, age, length of hospital-stay, CT grade of lung lesion, comorbidities, treatment, respiratory support, oxygen saturation and in-hospital outcomes were evaluated. The highest lung lesion volume during hospitalization was assessed. CT was performed upon admission and approximately every 5 days for evaluation of treatment. Statistical analysis was performed using the IBM SPSS Statistics software (IBM Corporation, USA). RESULTS: Patients with pulmonary cavitation significantly differed in age, SpO2, lung lesion volume, more common non-invasive ventilation and prolonged hospital-stay. Cardiovascular diseases were more common in both groups. Univariate logistic regression analysis revealed age, cardiovascular diseases, CT-based severity of lung damage, absence of biological therapy and non-invasive ventilation as risk factors of pulmonary cavitation. According to multivariate logistic regression analysis, these predictors were CT-based severity of lung damage and absence of biological therapy. Univariate logistic regression analysis showed that pulmonary cavitation had no significant effect on mortality (OR=2.613, 95% CI: 0.732-9.322, p=0.139). CONCLUSION: The risk of pulmonary cavitation in COVID-19 is directly related to advanced lung damage and untimely or absent biological therapy with IL-6 inhibitors. Pulmonary cavitation in COVID-19 is not a typical manifestation of disease and can be caused by some factors: fungal infection, secondary bacterial infection, tuberculosis and pulmonary infarction. Further study of this problem is required to develop diagnostic algorithms and treatment tactics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Retrospectivos , Idoso , Tomografia Computadorizada por Raios X/métodos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Índice de Gravidade de Doença , Tempo de Internação/estatística & dados numéricos , Adulto , Comorbidade
8.
Nanomaterials (Basel) ; 14(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38786831

RESUMO

Raman spectroscopy plays a pivotal role in spectroscopic investigations. The small Raman scattering cross-section of numerous analytes, however, requires enhancement of the signal through specific structuring of the electromagnetic and morphological properties of the underlying surface. This enhancement technique is known as surface-enhanced Raman spectroscopy (SERS). Despite the existence of various proposed alternatives, the approach involving Fabry-Pérot cavities, which constitutes a straightforward method to enhance the electromagnetic field around the analyte, has not been extensively utilized. This is because, for the analyte to experience the maximum electric field, it needs to be embedded within the cavity. Consequently, the top mirror of the cavity will eventually shield it from the external laser source. Recently, an open-cavity configuration has been demonstrated to exhibit properties similar to the classic Fabry-Pérot configuration, with the added advantage of maintaining direct accessibility for the laser source. This paper showcases how such a simple yet innovative configuration can be effectively utilized to achieve remarkable Raman enhancement. The simple structure, coupled with its inexpensive nature and versatility in material selection and scalability, makes it an ideal choice for various analytes and integration into diverse Raman apparatus setups.

9.
Biotechnol Bioeng ; 121(7): 2057-2066, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38650386

RESUMO

High hydrostatic pressure stabilized galactose oxidase (GaOx) at 70.0-80.0°C against thermal inactivation. The pseudo-first-order rate constant of inactivation kinact decreased by a factor of 8 at 80°C and by a factor of 44 at 72.5°C. The most pronounced effect of pressure was at the lowest studied temperature of 70.0°C with an activation volume of inactivation ΔV‡ of 78.8 cm3 mol-1. The optimal pressure against thermal inactivation was between 200 and 300 MPa. Unlike other enzymes, as temperature increased the ΔV‡ of inactivation decreased, and as pressure increased the activation energy of inactivation Eai increased. Combining the results for GaOx with earlier research on the pressure-induced stabilization of other enzymes suggests that ΔV‡ of inactivation correlates with the total molar volume of cavities larger than ~100 Å3 in enzyme monomers for enzymes near the optimal pH and whose thermal unfolding is not accompanied by oligomer dissociation.


Assuntos
Estabilidade Enzimática , Galactose Oxidase , Pressão Hidrostática , Galactose Oxidase/química , Galactose Oxidase/metabolismo , Temperatura Alta , Temperatura
10.
Chirurgie (Heidelb) ; 95(7): 546-554, 2024 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-38652249

RESUMO

BACKGROUND: The war in Ukraine has led to a strategic reorientation of the German Armed Forces towards national and alliance defense. This has also raised the need for medical and surgical adaptation to scenarios of conventional warfare. In order to develop appropriate and effective concepts it is necessary to identify those war injuries that are associated with a relevant primary and secondary mortality and that can be influenced by medical measures (potentially survivable injuries). OBJECTIVE: The aim of this selective literature review was to identify war injuries with high primary and secondary mortality. METHODS: A selective literature review was performed in the PubMed® database with the search terms war OR combat AND injury AND mortality from 2001 to 2023. Studies including data of war injuries and associated mortality were included. RESULTS: A total of 33 studies were included in the analysis. Severe traumatic brain injury and thoracoabdominal hemorrhage were the main contributors to primary mortality. Injuries to the trunk, neck, traumatic brain injury, and burns were associated with relevant secondary mortality. Among potentially survivable injuries, thoracoabdominal hemorrhage accounted for the largest proportion. Prehospital blood transfusions and short transport times significantly reduced war-associated mortality. CONCLUSION: Control of thoracoabdominal hemorrhage has the highest potential to reduce mortality in modern warfare. Besides that, treatment of traumatic brain injury, burns and neck injuries has a high relevance in reducing mortality. Hospitals of the German Armed Forces need to focus on these requirements.


Assuntos
Lesões Relacionadas à Guerra , Humanos , Ucrânia/epidemiologia , Lesões Relacionadas à Guerra/mortalidade , Lesões Relacionadas à Guerra/terapia , Guerra , Alemanha/epidemiologia , Lesões Encefálicas Traumáticas/mortalidade , Lesões Encefálicas Traumáticas/terapia , Medicina Militar
11.
Heliyon ; 10(7): e28612, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601601

RESUMO

In the present study, the sound absorption performance of inhomogeneous Micro-Perforated Panels (MPPs) with multiple cavities is investigated. Two models, a three-cavity system and a four-cavity system, are proposed and a numerical study is performed using MATLAB. The models are validated through experimental analysis in an impedance tube. The study meticulously varies the geometrical parameters, including pore diameter, thickness of the MPP, perforation ratio, and back-cavity length. It is found that MPPs with a greater number of sub-cavities have a better sound absorption coefficient than two-cavity systems. The results suggest that the back air cavity is predominantly responsible for multiple peaks, ensuring wideband sound absorption. It is also found that smaller perforation ratios for sub-cavities with larger pore diameters improve sound absorption performance in the lower frequency region. The study indicates that a pore diameter of less than 0.5 mm should be used for better sound absorption above the range of 800-850 Hz, and back cavity length has greater control than pore diameter between 850 Hz and 2000 Hz to make the curve smooth with less fluctuation. The findings have significant implications for the design of MPPs for real-world applications.

12.
Angew Chem Int Ed Engl ; 63(30): e202402973, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644341

RESUMO

Metal-Organic Frameworks can be grafted with amines by coordination to metal vacancies to create amine-appended solid adsorbents, which are being considered as an alternative to using aqueous amine solutions for CO2 capture. In this study, we propose an alternative mechanism that does not rely on the use of neutral metal vacancies as binding sites but is enabled by the structural adaptability of heterobimetallic Ti2Ca2 clusters. The combination of hard (Ti4+) and soft (Ca2+) metal centers in the inorganic nodes of the framework enables MUV-10 to adapt its pore windows to the presence of triethylenetetramine molecules. This dynamic cluster response facilitates the translocation and binding of tetraamine inside the microporous cavities to enable the formation of bis-coordinate adducts that are stable in water. The extension of this grafting concept from MUV-10 to larger cavities not restrictive to CO2 diffusion will complement other strategies available for the design of molecular sorbents for decarbonization applications.

13.
Int J Mol Sci ; 25(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38612388

RESUMO

Styryl dyes are generally poor fluorescent molecules inherited from their flexible molecular structures. However, their emissive properties can be boosted by restricting their molecular motions. A tight confinement into inorganic molecular sieves is a good strategy to yield highly fluorescent hybrid systems. In this work, we compare the confinement effect of two Mg-aluminophosphate zeotypes with distinct pore systems (the AEL framework, a one-dimensional channeled structure with elliptical pores of 6.5 Å × 4.0 Å, and the CHA framework, composed of large cavities of 6.7 Å × 10.0 Å connected by eight-ring narrower windows) for the encapsulation of 4-DASPI styryl dye (trans-4-[4-(Dimethylamino)styryl]-1-methylpyridinium iodide). The resultant hybrid systems display significantly improved photophysical features compared to 4-DASPI in solution as a result of tight confinement in both host inorganic frameworks. Molecular simulations reveal a tighter confinement of 4-DASPI in the elliptical channels of AEL, explaining its excellent photophysical properties. On the other hand, a singular arrangement of 4-DASPI dye is found when confined within the cavity-based CHA framework, where the 4-DASPI molecule spans along two adjacent cavities, with each aromatic ring sitting on these adjacent cavities and the polymethine chain residing within the narrower eight-ring window. However, despite the singularity of this host-guest arrangement, it provides less tight confinement for 4-DASPI than AEL, resulting in a slightly lower quantum yield.


Assuntos
Nanoporos , Corantes , Movimento (Física) , Extremidade Superior
14.
Plant Physiol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630866

RESUMO

Ginkgo (Ginkgo biloba L.) is one of the earliest extant species in seed plant phylogeny. Embryo development patterns can provide fundamental evidence for the origin, evolution, and adaptation of seeds. However, the architectural and morphological dynamics during embryogenesis in Ginkgo biloba (G. biloba) remain elusive. Herein, we obtained over 2200 visual slices from three stages of embryo development using micro-computed tomography imaging with improved staining methods. Based on 3D spatio-temporal pattern analysis, we found that a shoot apical meristem with seven highly differentiated leaf primordia, including apical and axillary leaf buds, is present in mature Ginkgo embryos. 3D rendering from the front, top, and side views showed two separate transport systems of tracheids located in the hypocotyl and cotyledon, representing a unique pattern of embryogenesis. Furthermore, the morphological dynamic analysis of secretory cavities indicated their strong association with cotyledons during development. In addition, we identified genes GbLBD25a (lateral organ boundaries domain 25a), GbCESA2a (cellulose synthase 2a), GbMYB74c (myeloblastosis 74c), GbPIN2 (PIN-FORMED 2) associated with vascular development regulation, and GbWRKY1 (WRKYGOK 1), GbbHLH12a (basic helix-loop-helix 12a), GbJAZ4 (jasmonate zim-domain 4) potentially involved in the formation of secretory cavities. Moreover, we found that flavonoid accumulation in mature embryos could enhance post-germinative growth and seedling establishment in harsh environments. Our 3D spatial reconstruction technique combined with multi-omics analysis opens avenues for investigating developmental architecture and molecular mechanisms during embryogenesis and lays the foundation for evolutionary studies of embryo development and maturation.

15.
Clin Anat ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634327

RESUMO

PURPOSE: The preserved head of King Henri IV of France (life 1553-1610, reign 1589-1610) has survived to the present day thanks to high-quality embalming and favorable conservation conditions. The aim of this study was to examine Henry IV's upper resonant cavities and mastoids using an original and innovative forensic three-dimensional segmentation method. METHODS: The paranasal sinuses and mastoid cells of King Henri IV of France were studied by cross-referencing available biographical information with clinical and flexible endoscopic examination and computed tomography (CT-scan) imaging. The paranasal sinuses and mastoid cells were delineated and their volumes were assessed using ITK-SNAP 4.0 software (open-source). Graphical representations were created using Fusion 360® (Autodesk Inc., San Rafael, CA, USA) and MeshMixer® (Autodesk Inc., San Rafael, CA, USA). RESULTS: Paranasal sinus tomodensitometry revealed abnormalities in shape and number. Henri IV of France suffered from sinus aplasia. Neither the left sphenoid nor left frontal sinus contrasted sharply, and a remarkable pneumatization of the right clinoid processes extended throughout the height of the right pterygoid process. The total volumes of Henri IV's mastoid air-cells were estimated at 27 and 26 mL, respectively, for the right and left sides, exceeding the normal mean and the maximum of modern subjects by a wide margin. No sign of chronic ear or sinus condition was found. CONCLUSIONS: An innovative method has been developed in forensic medicine to establish hypotheses about the growth and respiratory conditions of the face.

16.
Cureus ; 16(3): e56071, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618331

RESUMO

Objective In light of several advancements and considerations in endodontic dentistry, there still remains a need to comprehensively evaluate the outcome disparities between repairing and replacing broken dental restorations. This study aims to compare the effectiveness of repairing dental restorations versus replacing them, focusing on how each method affects the structural strength and longevity of the restorations. Methods The study included 60 freshly removed human maxillary premolars. Initial processing involved rigorous washing, descaling, and polishing of the teeth. To ensure preservation, the specimens were stored in sterile, distilled water. To occlude the root canals, a self-hardening composite resin was used, and the roots were coated with two coats of clear nail polish to prevent moisture penetration. A 245 carbide bur attached to a high-speed dental handpiece with air and water spray cooling produced standardized Class II cavities on the occluso-proximal surfaces. Each cavity had a buccolingual breadth of 2 mm, an occluso-cervical length of 4 mm, and a gingival boundary that was 1 mm coronal to the cement-enamel junction. Following this preparation, the teeth were randomly separated into three groups (Group A, Group B, and Group C), each containing 20 teeth. Results Our analysis showed that teeth with entirely replaced restorations had a higher average fracture resistance than those with repaired restorations. However, the difference in fracture resistance between the repair and replacement groups for each type of material was not statistically significant. Conclusion Based on the findings, repairing a dental restoration can be a conservative and less invasive alternative to a full replacement without a significant compromise in the restoration's ability to withstand fracture. Therefore, dental professionals might consider full restoration as a viable option, taking into account the need to preserve dental tissue as well as the restoration's durability and structural integrity.

17.
BMC Bioinformatics ; 25(1): 172, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689238

RESUMO

BACKGROUND: Protein-protein interactions (PPIs) are conveyed through binding interfaces or surface patches on proteins that become buried upon binding. Structural and biophysical analysis of many protein-protein interfaces revealed certain unique features of these surfaces that determine the energetics of interactions and play a critical role in protein evolution. One of the significant aspects of binding interfaces is the presence of binding hot spots, where mutations are highly deleterious for binding. Conversely, binding cold spots are positions occupied by suboptimal amino acids and several mutations in such positions could lead to affinity enhancement. While there are many software programs for identification of hot spot positions, there is currently a lack of software for cold spot detection. RESULTS: In this paper, we present Cold Spot SCANNER, a Colab Notebook, which scans a PPI binding interface and identifies cold spots resulting from cavities, unfavorable charge-charge, and unfavorable charge-hydrophobic interactions. The software offers a Py3DMOL-based interface that allows users to visualize cold spots in the context of the protein structure and generates a zip file containing the results for easy download. CONCLUSIONS: Cold spot identification is of great importance to protein engineering studies and provides a useful insight into protein evolution. Cold Spot SCANNER is open to all users without login requirements and can be accessible at: https://colab. RESEARCH: google.com/github/sagagugit/Cold-Spot-Scanner/blob/main/Cold_Spot_Scanner.ipynb .


Assuntos
Proteínas , Software , Proteínas/química , Proteínas/metabolismo , Mapeamento de Interação de Proteínas/métodos , Ligação Proteica , Conformação Proteica , Modelos Moleculares , Sítios de Ligação , Interações Hidrofóbicas e Hidrofílicas
18.
Neotrop Entomol ; 53(3): 552-567, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38684598

RESUMO

Solitary bees and wasps that nest in cavities in tree trunks are important components of terrestrial ecosystems, providing pollination services, and in the case of wasps, the regulation of their prey populations. However, little is known about the vertical strata where bees and wasps build their nests. This is especially the case of urban forest remnants in the Amazon, which is relevant in the context of the global crisis in insect losses. We investigated the existence of vertical stratification in the nesting of solitary bees and wasps in an urban forest in Rio Branco, state of Acre, in the western Brazilian Amazon. We focused on whether wood temperature, ants, and termites are predictors of bee and wasp nesting. We sampled bee and wasp nests in the forest using trap-nests made with wooden blocks containing cavities with three different diameters for twelve months. Trap-nests were installed randomly at three heights in the forest. We collected 145 nests of 25 species, belonging to 11 genera and 6 families. A higher number of nests and species were collected in the upper stratum of the forest, strengthening the hypothesis that there is vertical stratification in the assemblage of solitary bees and wasps. Wood surface temperature and termite attacks on trap-nests were significantly different between strata, which may explain the vertical stratification of bee and wasp assemblages. Considering the importance of these insects for tropical forest ecosystems, the conservation of structurally complex and stratified forests is of paramount importance to maintain the diversity of this insect group.


Assuntos
Florestas , Vespas , Animais , Brasil , Abelhas/classificação , Vespas/fisiologia , Vespas/classificação , Comportamento de Nidação , Temperatura
19.
Nanomaterials (Basel) ; 14(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38607115

RESUMO

Efficient solar thermal conversion is crucial for renewable clean energy technologies such as solar thermal power generation, solar thermophotovoltaic and seawater desalination. To maximize solar energy conversion efficiency, a solar selective absorber with tailored absorption properties designed for solar applications is indispensable. In this study, we propose a broadband selective absorber based on amorphous carbon (a-C) metamaterials that achieves high absorption in the ultraviolet (UV), visible (Vis) and near-infrared (NIR) spectral ranges. Additionally, through metal doping, the optical properties of carbon matrix materials can be modulated. We introduce Ti@a-C thin film into the nanostructure to enhance light absorption across most of the solar spectrum, particularly in the NIR wavelength band, which is essential for improving energy utilization. The impressive solar absorptivity and photothermal conversion efficiency reach 97.8% and 95.6%, respectively. Notably, these superior performances are well-maintained even at large incident angles with different polarized states. These findings open new avenues for the application of a-C matrix materials, especially in fields related to solar energy harvesting.

20.
Cureus ; 16(3): e55839, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463409

RESUMO

Atraumatic splenic rupture is a serious intraabdominal emergency that requires emergent intervention. This can be due to a number of causes. In this case report, we introduce a rare cause of atraumatic splenic rupture, which is an otherwise benign asymptomatic disease that only manifests clinically upon rupture, namely splenic peliosis. There is limited existing knowledge concerning the disease's etiology and diagnosis; however, this study presents the possible etiological explanations, associated risk factors, and possible radiologic diagnostic modalities.

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