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1.
Environ Res ; 251(Pt 2): 118746, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38513751

RESUMEN

Understanding the relative role of dispersal dynamics and niche constraints is not only a core task in community ecology, but also becomes an important prerequisite for bioassessment. Despite the recent progress in our knowledge of community assembly in space and time, patterns and processes underlying biotic communities in alpine glacierized catchments remain mostly ignored. To fill this knowledge gap, we combined the recently proposed dispersal-niche continuum index (DNCI) with traditional constrained ordinations and idealized patterns of species distributions to unravel community assembly mechanisms of different key groups of primary producers and consumers (i.e., phytoplankton, epiphytic algae, zooplankton, macroinvertebrates, and fishes) in rivers in the Qinghai-Tibet Plateau, the World's Third Pole. We tested whether organismal groups with contrasting body sizes differed in their assembly processes, and discussed their applicability in bioassessment in alpine zones. We found that community structure of alpine river biotas was always predominantly explained in terms of dispersal dynamics and historical biogeography. These patterns are most likely the result of differences in species-specific functional attributes, the stochastic colonization-extinction dynamics driven by multi-year glacier disturbances and the repeated hydrodynamic separation among alpine catchments after the rising of the Qilian mountains. Additionally, we found that the strength of dispersal dynamics and niche constraints was partially mediated by organismal body sizes, with dispersal processes being more influential for microscopic primary producers. Finding that zooplankton and macroinvertebrate communities followed clumped species replacement structures (i.e., Clementsian gradients) supports the notion that environmental filtering also contributes to the structure of high-altitude animal communities in glacierized catchments. In terms of the applied fields, we argue that freshwater bioassessment in glacierized catchments can benefit from incorporating the metacommunity perspective and applying novel approaches to (i) detect the optimal spatial scale for species sorting and (ii) identify and eliminate the species that are sensitive to dispersal-related processes.


Asunto(s)
Ríos , Animales , Tibet , Zooplancton/fisiología , Zooplancton/clasificación , Invertebrados/fisiología , Cubierta de Hielo , Peces/fisiología , Ecosistema , Organismos Acuáticos , Biota , Fitoplancton/fisiología , Biodiversidad , Distribución Animal
2.
J Chem Phys ; 161(3)2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39007392

RESUMEN

Silicon, renowned for its remarkable energy density, has emerged as a focal point in the pursuit of high-energy storage solutions for the next generation. Nevertheless, silicon electrodes are known to undergo significant volume expansion during the insertion of lithium ions, leading to structural deformation and the development of internal stresses, and causing a rapid decline in battery capacity and overall lifespan. To gain deeper insights into the intricacies of charge rate effects, this study employs a combination of in situ measurements and computational modeling to elucidate the cyclic performance of composite silicon electrodes. The findings derived from the established model and curvature measurement system unveil the substantial alterations in stress and deformation as a consequence of varying charge rates. Notably, the active layer experiences compressive forces that diminish as the charge rate decreases. At a charge rate of 0.2, the active layer endures a maximum stress of 89.145 MPa, providing a comprehensive explanation for the observed deterioration in cycling performance at higher charge rates. This study not only establishes a fundamental basis for subsequent stress analyses of silicon electrodes but also lays a solid foundation for further exploration of the impact of charge rates on composite silicon electrodes.

3.
Dermatol Surg ; 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38574349

RESUMEN

BACKGROUND: Mohs surgery of eyelid skin cancers requires detailed knowledge of anatomy for precise surgery and accurate evaluation of histology. OBJECTIVE: To review the histology of the peritarsal eyelid using frozen sections as encountered intraoperatively by Mohs surgeons. METHODS: The authors review the literature describing the anatomy and histology of the peritarsal eyelid from the lens of a Mohs surgeon. Histology from select Mohs cases is used to frame the discussion of the microanatomy of this region. RESULTS: The peritarsal eyelids contain a unique mixture of skin, muscle, tarsus, glandular tissue, and conjunctiva. The histologic appearance of many of these structures differs from skin found outside of this anatomic region. Tumors of the eyelid and periocular region may mimic normal histologic structures found within the peritarsal eyelid. CONCLUSION: The peritarsal eyelids have unique anatomy and associated histologic structures. Knowledge of the detailed histoanatomy is required for confident execution of Mohs surgery in this anatomic region.

4.
Dermatol Surg ; 49(12): 1066-1071, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-38019008

RESUMEN

BACKGROUND: Mohs micrographic surgery may be discontinued with positive margins as an anticipated strategy for multidisciplinary care or as an unanticipated occurrence. Management of primary tumors has not been compared after anticipated versus unanticipated incomplete Mohs micrographic surgery (iMMS). OBJECTIVE: To compare rates and timing of adjuvant surgery after iMMS and final margin status when iMMS is anticipated versus unanticipated. Secondary outcomes were preoperative and intraoperative clinicopathologic factors associated with iMMS. METHODS: Cases of iMMS of keratinocyte carcinomas at a tertiary academic center between 2005 and 2022 were classified as anticipated (preoperative assembly of multidisciplinary teams) or unanticipated (ad hoc management of positive margins). Rate, timing, and final margin status of adjuvant surgery was compared between anticipated and unanticipated iMMS cohorts using χ2/Fisher exact test for categorical variables and t-test for continuous variables. RESULTS: Of 127 iMMS cases, 51.2% (65/127) were anticipated. Anticipated iMMS cases were more likely to undergo additional resection (98.5% vs 72.6%, p < .001), with fewer delays (3.9 vs 13.2 days, p < .001) and higher rates of final margin clearance (84.6% vs 59.7%, p < .001). CONCLUSION: When iMMS is anticipated as part of multidisciplinary care, patients are more likely to undergo additional resection, with fewer delays to next surgery and higher final margin clearance rates.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Cirugía de Mohs , Tiempo de Tratamiento , Resultado del Tratamiento , Carcinoma Basocelular/cirugía , Carcinoma Basocelular/patología , Márgenes de Escisión , Estudios Retrospectivos
5.
Phys Chem Chem Phys ; 24(48): 29279-29297, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36268731

RESUMEN

From the overall framework of battery development, the battery structures have not received enough attention compared to the chemical components in batteries. The mechanical-electrochemical coupling behavior is a starting point for investigation on battery structures and the subsequent battery design. This perspective systematically reviews the efforts on the mechanics-based design for lithium-ion batteries (LIBs). Two typical types of mechanics-based LIB designs, namely the design at the preparation stage and that at the cycling stage, have been discussed, respectively. The former systemizes the structure design of multiscale battery components from the particle level to the cell level. The latter focuses on the external mechanics-related control, including external pressures and charge-discharge protocols, of in-service LIBs. Moreover, the general problems currently being faced in the mechanics-based LIB design are summarized, followed by the outlook of possible solutions.

6.
Phys Chem Chem Phys ; 24(41): 25580-25587, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36254690

RESUMEN

The applications of silicon (Si)-based electrodes in lithium ion batteries have been impeded by mechanical degradation caused by lithiation/delithiation-induced volume changes. Understanding the evolution of mechanical behavior and properties of Si composite electrodes during electrochemical cycling is indispensable to develop coping strategies and predict battery life. In this study, we optimized an in situ method for measuring electro-chemo-mechanical properties, including partial molar volume, elastic modulus, and electrochemical reaction-induced stress, based on the curvature changes of cantilever electrodes. We found that the swell strain and partial molar volume of Si electrodes increase with the Li concentration. The elastic modulus generally decreases with the Li concentration. The in-plain stress transforms from tensile stress to compressive stress and showed an increasing tendency during further lithiation, while it shows a reverse trend during delithiation. The stress evolution correlates well with the "opening" and "closing" of micro-cracks in Si composite electrodes during cycling. These findings provide not only input parameters for battery modeling but also help understand the capacity fading of Si electrodes. Furthermore, the in situ measurement methodology developed in this study is readily applied to other battery electrodes.

7.
Dermatol Surg ; 48(4): 418-422, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35165219

RESUMEN

BACKGROUND: The relationship of postoperative facial scar assessments among patients, physicians, and societal onlookers is not clearly defined. OBJECTIVE: To identify differences in perceived scar outcomes by different stakeholders. METHODS AND MATERIALS: Retrospective cohort study at a single Mohs micrographic surgery (MMS) center during which scars were assessed by: patients, physicians, and medical student observers not involved in patients' care using the Patient and Observer Scar Assessment Scale (v.2). Eighty-one patients graded their scars at 2 visits: 1 to 2 weeks post-MMS and 3 months post-MMS. Deidentified patient photographs were taken at each visit and graded by 4 physicians and 12 observers. RESULTS: At week 1, there was a significant difference in overall opinion of scar appearance between patient and physicians (p = .001) and medical student observers and physicians (p < .001). Physicians graded scars more favorably. At 3 months, there remained a difference in scar evaluations between patient and physicians (p = .005), whereas medical student observers rated scars more similarly to physicians (p = .404). CONCLUSION: Postoperative scar perceptions differ among stakeholders. Physicians must be mindful of this disparity when counseling patients in the perioperative setting to align patient expectations with realistic scar outcomes.


Asunto(s)
Médicos , Estudiantes de Medicina , Cicatriz/etiología , Cicatriz/patología , Humanos , Cirugía de Mohs/efectos adversos , Cirugía de Mohs/métodos , Estudios Retrospectivos
8.
Sensors (Basel) ; 22(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35458913

RESUMEN

Accurate fire identification can help to control fires. Traditional fire detection methods are mainly based on temperature or smoke detectors. These detectors are susceptible to damage or interference from the outside environment. Meanwhile, most of the current deep learning methods are less discriminative with respect to dynamic fire and have lower detection precision when a fire changes. Therefore, we propose a dynamic convolution YOLOv5 fire detection method using a video sequence. Our method first uses the K-mean++ algorithm to optimize anchor box clustering; this significantly reduces the rate of classification error. Then, the dynamic convolution is introduced into the convolution layer of YOLOv5. Finally, pruning of the network heads of YOLOv5's neck and head is carried out to improve the detection speed. Experimental results verify that the proposed dynamic convolution YOLOv5 fire detection method demonstrates better performance than the YOLOv5 method in recall, precision and F1-score. In particular, compared with three other deep learning methods, the precision of the proposed algorithm is improved by 13.7%, 10.8% and 6.1%, respectively, while the F1-score is improved by 15.8%, 12% and 3.8%, respectively. The method described in this paper is applicable not only to short-range indoor fire identification but also to long-range outdoor fire detection.


Asunto(s)
Incendios , Robótica , Algoritmos , Redes Neurales de la Computación , Humo
9.
J Nanobiotechnology ; 19(1): 323, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34654435

RESUMEN

Knocking down the oncogene ROC1 with siRNA inhibits the proliferation of cancer cells by suppressing the Neddylation pathway. However, methods for delivering siRNA in vivo to induce this high anticancer activity with low potential side effects are urgently needed. Herein, a folic acid (FA)-modified polydopamine (PDA) nanomedicine used in photothermal therapy was designed for siRNA delivery. The designed nanovector can undergo photothermal conversion with good biocompatibility. Importantly, this genetic nanomedicine was selectively delivered to liver cancer cells by FA through receptor-mediated endocytosis. Subsequently, the siRNA cargo was released from the PDA nanomedicine into the tumor microenvironment by controlled release triggered by pH. More importantly, the genetic nanomedicine not only inhibited liver cancer cell proliferation but also promoted liver cell apoptosis by slowing ROC1 activity, suppressing the Neddylation pathway, enabling the accumulation of apototic factor ATF4 and DNA damage factor P-H2AX. Combined with photothermal therapy, this genetic nanomedicine showed superior inhibition of the growth of liver cancer in vitro and in vivo. Taken together, the results indicate that this biodegradable nanomedicine exhibits good target recognition, an effective pH response, application potential for genetic therapy, photothermal imaging and treatment of liver cancer. Therefore, this work contributes to the design of a multifunctional nanoplatform that combines genetic therapy and photothermal therapy for the treatment of liver cancer.


Asunto(s)
Proteínas Portadoras/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína NEDD8/metabolismo , Sistema de Administración de Fármacos con Nanopartículas , ARN Interferente Pequeño/metabolismo , Animales , Proteínas Portadoras/genética , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Humanos , Indoles/química , Masculino , Ratones , Ratones Desnudos , Proteína NEDD8/genética , Nanomedicina , Terapia Fototérmica , Polímeros/química , ARN Interferente Pequeño/genética
10.
Environ Sci Technol ; 54(18): 11127-11136, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32794702

RESUMEN

Formation of halogenated disinfection byproducts (DBPs) from pharmaceutically active compounds has been observed in water supply systems following wastewater chlorination. Although research has been limited thus far, several studies have shown that halogenated DBPs may elicit increased toxicity compared to their parent compounds. For example, the lipid regulator gemfibrozil has been shown to form chlorogemfibrozil (Cl-gemfibrozil) and bromogemfibrozil (Br-gemfibrozil) following chlorination, which are more potent antiandrogens in male Japanese medaka (Oryzias latipes) compared to their parent compounds. In the present study, we aimed to characterize the bioaccumulative ability of halogenated gemfibrozil DBPs in marine polychaetes via chronic sediment exposures and, consequently, to assess the chronic and acute toxicity of halogenated gemfibrozil DBPs through sediment (in vivo) and aqueous (in vivo and in silico) toxicity evaluations. Following 28 day sediment exposures, Cl-gemfibrozil and Br-gemfibrozil bioaccumulated within Neanthes arenaceodentata, with both compounds reducing survival and growth. The biota-sediment accumulation factors determined for Cl-gemfibrozil and Br-gemfibrozil were 2.59 and 6.86, respectively. Furthermore, aqueous 96 h toxicity tests with N. arenaceodentata indicated that gemfibrozil DBPs elicited increased toxicity compared to the parent compound. While gemfibrozil had an acute LC50 value of 469.85 ± 0.096 mg/L, Cl-gemfibrozil and Br-gemfibrozil had LC50 values of 12.34 ± 0.085 and 9.54 ± 0.086 mg/L, respectively. Although acute toxicity is relatively low, our results indicate that halogenated gemfibrozil DBPs are bioaccumulative and may elicit effects in apex food web organisms prone to accumulation following lifelong exposures.


Asunto(s)
Desinfectantes , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Purificación del Agua , Animales , Desinfección , Gemfibrozilo/toxicidad , Halogenación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 879-884, 2019 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-31631639

RESUMEN

Radiotherapy is one of the main treatments for tumor with increasingly high request for technique precision and the equipment stability. Machine learning may bring radiotherapy simplicity, individualization and precision, and may improve the automatic level of planning and quality assurance. Based on the process of radiotherapy, this paper reviews the applications and researches on machine learning, with an emphasis on deep learning, and proposes the prospects in the following aspects: segmentation of normal tissue and tumor, planning, treatment delivery, quality assurance and prognosis prediction.


Asunto(s)
Aprendizaje Automático , Neoplasias/radioterapia , Aprendizaje Profundo , Humanos
15.
J Am Acad Dermatol ; 78(6): 1060-1067, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29518455

RESUMEN

BACKGROUND: Changes in patient perceptions of quality of life (QOL) after Mohs micrographic surgery (MMS) may benefit from different counseling or treatment. OBJECTIVE: To measure QOL before and after MMS and to identify risk factors associated with impaired QOL. METHODS: Prospective observational study of 727 patients with skin cancer who self-reported QOL via the Skin Cancer Index immediately before and at 1 to 2 weeks and 3 months after MMS. RESULTS: QOL fluctuated after MMS. At 1 to 2 weeks after surgery, overall QOL remained unchanged compared with before MMS. Patients reported reduced anxiety about skin cancer but had increased distress about social interactions and physical appearance. At 3 months after surgery, patients reported an overall improvement in QOL compared with before MMS (P = .0007). Age younger than 65 years (P = .0001), female sex (P = .0001), and tobacco use (P = .03) were associated with lower QOL scores at all assessment points. LIMITATIONS: Single-site observational study. Significant loss to follow-up at both time points after MMS. CONCLUSION: Patients with skin cancer had persistent concerns about social interactions and physical appearance 1 to 2 weeks after MMS, but all aspects of their QOL improved by 3 months after surgery. Patients who underwent MMS that were younger than 65 years, were female, or smoked were at increased risk for longitudinally impaired QOL.


Asunto(s)
Ansiedad/psicología , Imagen Corporal/psicología , Cirugía de Mohs/psicología , Calidad de Vida , Neoplasias Cutáneas/cirugía , Anciano , Estética , Femenino , Humanos , Relaciones Interpersonales , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Cirugía de Mohs/métodos , Medición de Resultados Informados por el Paciente , Atención Perioperativa , Estudios Prospectivos , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/psicología , Estadísticas no Paramétricas , Factores de Tiempo
20.
J Am Acad Dermatol ; 75(4): 688-695, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27421628

RESUMEN

BACKGROUND: No evidence-based surgical guidelines exist for atypical intraepidermal melanocytic proliferation (AIMP), a descriptive histopathologic diagnosis with uncertain malignant potential. OBJECTIVE: We sought to identify the frequency of and risk factors associated with positive or equivocal margins after conventional excision. METHODS: We conducted a retrospective cross-sectional study of 413 AIMPs treated by conventional excision. RESULTS: Positive or equivocal margins were seen in 2.9% (12/413) of conventional excisions of AIMP. Risk factors associated with positive or equivocal margins included anatomic location on the head and neck (5/51, 9.8%; odds ratio 6.91, 95% confidence interval 1.93-24.80) (P = .012) and a preoperative biopsy specimen that included melanoma in situ in the differential diagnosis (11/214, 5.1%; odds ratio 10.73, 95% confidence interval 1.37-83.88) (P = .006). The frequency of positive or equivocal margins did not differ significantly with surgical margins greater than or less than 5 mm (odds ratio 0.61, 95% confidence interval 0.18-2.07) (P = .457). LIMITATIONS: This was a single-site, retrospective observational study. CONCLUSION: AIMP has a significantly increased risk for incomplete excision when it is located on the head and neck or has a preoperative histologic differential diagnosis that includes melanoma in situ. These subsets of AIMP may benefit from Mohs micrographic surgery or staged surgical excision to confirm clear margins before reconstruction.


Asunto(s)
Melanoma/patología , Melanoma/cirugía , Cirugía de Mohs/efectos adversos , Recurrencia Local de Neoplasia/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Centros Médicos Académicos , Adulto , Anciano , Biopsia con Aguja , Intervalos de Confianza , Estudios Transversales , Femenino , Humanos , Inmunohistoquímica , Modelos Logísticos , Masculino , Melanocitos/patología , Melanoma/mortalidad , Persona de Mediana Edad , Cirugía de Mohs/métodos , Recurrencia Local de Neoplasia/epidemiología , Siembra Neoplásica , Oportunidad Relativa , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Neoplasias Cutáneas/mortalidad , Análisis de Supervivencia , Adulto Joven , Melanoma Cutáneo Maligno
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