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1.
BMC Geriatr ; 24(1): 545, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914987

RESUMEN

BACKGROUND: Late-life depression (LLD) is a prevalent neuropsychiatric disorder in the older population. While LLD exhibits high mortality rates, depressive symptoms in older adults are often masked by physical health conditions. In younger adults, depression is associated with deficits in pupil light reflex and eye blink rate, suggesting the potential use of these responses as biomarkers for LLD. METHODS: We conducted a study using video-based eye-tracking to investigate pupil and blink responses in LLD patients (n = 25), older (OLD) healthy controls (n = 29), and younger (YOUNG) healthy controls (n = 25). The aim was to determine whether there were alterations in pupil and blink responses in LLD compared to both OLD and YOUNG groups. RESULTS: LLD patients displayed significantly higher blink rates and dampened pupil constriction responses compared to OLD and YOUNG controls. While tonic pupil size in YOUNG differed from that of OLD, LLD patients did not exhibit a significant difference compared to OLD and YOUNG controls. GDS-15 scores in older adults correlated with light and darkness reflex response variability and blink rates. PHQ-15 scores showed a correlation with blink rates, while MoCA scores correlated with tonic pupil sizes. CONCLUSIONS: The findings demonstrate that LLD patients display altered pupil and blink behavior compared to OLD and YOUNG controls. These altered responses correlated differently with the severity of depressive, somatic, and cognitive symptoms, indicating their potential as objective biomarkers for LLD.


Asunto(s)
Parpadeo , Depresión , Reflejo Pupilar , Humanos , Masculino , Anciano , Femenino , Parpadeo/fisiología , Reflejo Pupilar/fisiología , Depresión/fisiopatología , Depresión/psicología , Anciano de 80 o más Años , Persona de Mediana Edad , Adulto , Pupila/fisiología , Oscuridad , Adulto Joven , Luz
2.
Materials (Basel) ; 17(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38930384

RESUMEN

Barium zirconate (BaZrO3, BZO), which exhibits superior mechanical, thermal, and chemical stability, has been widely used in many applications. In dentistry, BZO is used as a radiopacifier in mineral trioxide aggregates (MTAs) for endodontic filling applications. In the present study, BZO was prepared using the sol-gel process, followed by calcination at 700-1000 °C. The calcined BZO powders were investigated using X-ray diffraction and scanning electron microscopy. Thereafter, MTA-like cements with the addition of calcined BZO powder were evaluated to determine the optimal composition based on radiopacity, diametral tensile strength (DTS), and setting times. The experimental results showed that calcined BZO exhibited a majority BZO phase with minor zirconia crystals. The crystallinity, the percentage, and the average crystalline size of BZO increased with the increasing calcination temperature. The optimal MTA-like cement was obtained by adding 20% of the 700 °C-calcined BZO powder. The initial and final setting times were 25 and 32 min, respectively. They were significantly shorter than those (70 and 56 min, respectively) prepared with commercial BZO powder. It exhibited a radiopacity of 3.60 ± 0.22 mmAl and a DTS of 3.02 ± 0.18 MPa. After 28 days of simulated oral environment storage, the radiopacity and DTS decreased to 3.36 ± 0.53 mmAl and 2.84 ± 0.27 MPa, respectively. This suggests that 700 °C-calcined BZO powder has potential as a novel radiopacifier for MTAs.

3.
Nanomaterials (Basel) ; 14(11)2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869559

RESUMEN

This study developed a DC-free technique that used dark-mode scanning capacitance microscopy (DM-SCM) with a small-area contact electrode to evaluate and image equivalent oxide thicknesses (EOTs). In contrast to the conventional capacitance-voltage (C-V) method, which requires a large-area contact electrode and DC voltage sweeping to provide reliable C-V curves from which the EOT can be determined, the proposed method enabled the evaluation of the EOT to a few nanometers for thermal and high-k oxides. The signal intensity equation defining the voltage modulation efficiency in scanning capacitance microscopy (SCM) indicates that thermal oxide films on silicon can serve as calibration references for the establishment of a linear relationship between the SCM signal ratio and the EOT ratio; the EOT is then determined from this relationship. Experimental results for thermal oxide films demonstrated that the EOT obtained using the DM-SCM approach closely matched the value obtained using the typical C-V method for frequencies ranging from 90 kHz to 1 MHz. The percentage differences in EOT values between the C-V and SCM measurements were smaller than 0.5%. For high-k oxide films, DM-SCM with a DC-free operation may mitigate the effect of DC voltages on evaluations of EOTs. In addition, image operations were performed to obtain EOT images showing the EOT variation induced by DC-stress-induced charge trapping. Compared with the typical C-V method, the proposed DM-SCM approach not only provides a DC-free approach for EOT evaluation, but also offers a valuable opportunity to visualize the EOT distribution before and after the application of DC stress.

4.
Bioresour Technol ; 406: 130912, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38821424

RESUMEN

Addressing geogenic and anthropogenic arsenic (As) pollution is critical for environmental health. This study explored arsenite [As(III)] removal using Cyanidiales, particularly Cyanidium caldarium (Cc) and Galdieria partita (Gp), under acidic to neutral pH, and determined As(III) detoxification mechanisms in relation to As speciation and protein secondary structure in Cyanidiales. Regarding As(III) sorption amounts, Cc outperformed Gp, reaching 83.2 mg g-1 of removal at pH 5.0. Wherein, 23.5 % of sorbed As on Cc presented as arsenate [As(V)] complexation with polysaccharides, alongside other predominant species including As(III)-cysteine (41.2 %) and As(III)-polysaccharides (35.3 %) complexes. This suggested that As(III) was directly transported into cells, rather than As(V). Coupled with the formation of As(III)-cysteine complexes within cells, these mechanisms may be key to efficiently accumulating As(III) in Cyanidiales during the 6-h incubation. These results highlight the potential of Cyanidiales for sustainable As(III) remediation and provide new insights into managing As(III) toxicity.

6.
J Gastrointest Surg ; 28(1): 40-46, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38353073

RESUMEN

BACKGROUND: Older age and frailty are associated with worse postoperative outcomes and prolonged length of stay (LOS). In this study, we aimed to analyze the long-term outcomes after the implementation of our geriatric surgical service (GSS). METHODS: This was a single-center retrospective study from July 2010 to December 2021 on patients aged ≥75 years or patients aged ≥65 years with frailty. Our GSS includes multidisciplinary assessment and optimization by specialized nurses, physiotherapists, anesthetists, dietitians, and geriatricians. Cumulative sum (CUSUM) analysis was used to assess the performance of our GSS. Our primary outcome was defined as the presence of 30-day mortality, prolonged LOS ≥ 14 days, and/or >10% decrease in the modified Barthel Index at 6 weeks, which depicts the failure of GSS. A downsloping CUSUM curve implies consecutive cases of success. RESULTS: There were 233 patients with a mean age of 79.0 ± 4.9 years; of these, 73 patients (31.3%) were frail. The overall 30-day mortality (1.7%), Clavien-Dindo ≥ grade IIIA complications (12.0%), and LOS (median, 7.0 days) were low. The CUSUM analysis showed 3 phases with overall sustained improvement in outcomes. Transient inconsistency in the second phase (during midimplementation of GSS) may be due to the early adoption of laparoscopic surgery (44.6% vs 24.1%; adjusted P =.031) and expansion of service to include patients with higher perioperative risks (weighted Charlson Comorbidity Index score ≥4: 64.9% vs 38.0%; adjusted P =.002) in the second period compared with the first period. The outcomes subsequently improved in the third phase after overcoming the learning curve. CONCLUSION: Our GSS showed sustained performance over the past decade. Good quality surgery and surgeon-led geriatric service are paramount for good postoperative outcomes.


Asunto(s)
Neoplasias Colorrectales , Procedimientos Quirúrgicos del Sistema Digestivo , Fragilidad , Cirujanos , Humanos , Anciano , Anciano de 80 o más Años , Estudios Retrospectivos , Tiempo de Internación , Neoplasias Colorrectales/cirugía , Complicaciones Posoperatorias/epidemiología , Evaluación Geriátrica
7.
Acta Neurochir (Wien) ; 166(1): 111, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411767

RESUMEN

BACKGROUND: Spinal dural arteriovenous fistula (sDAVF) is a rare vascular malformation that leads to serious neurological symptoms. We treat a 52-year-old man with sDAVF in the thoracic segment exhibiting uncoordinated gait. METHOD: Thoracic MRI of the lesion indicated myelomalacia and dilated blood vessels, while DSA revealed the right T6 radicular artery as the feeding arteriole. A full endoscopic obliteration of the lesion was performed under angiography guidance in a hybrid operation room. CONCLUSION: The case underscores the importance of a multidisciplinary and individualized approach to successfully manage sDAVF using a fully endoscopic approach.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Enfermedades de la Médula Espinal , Masculino , Humanos , Persona de Mediana Edad , Endoscopía , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Angiografía , Arterias
8.
J Plast Reconstr Aesthet Surg ; 88: 153-160, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37980788

RESUMEN

BACKGROUND: Anterolateral thigh (ALT) flaps have several anatomical variations and clinical uses. Here, a simplified classification and economical application are introduced. METHODS: A total of 168 ALT flap reconstructions performed between January 2013 and December 2016 were reviewed. Vascular anatomy of the flaps was classified into 5 types: type I (single perforator from the transverse branch), type II (single perforator from the descending branch), type III (multiple perforators from the transverse branch), type IV (multiple perforators from the descending branch), and type V (multiple perforators from both branches). Furthermore, flaps harvested via preservation of the proximal perforator were compared with those that were not. RESULTS: Vascular classification revealed that type IV (50.0%) and type V (32.1%) flaps were the most commonly used. Of these, 50.0% of type IV and 79.6% of type V were harvested as proximal-perforator-preserving distal ALT flaps. The proximal-perforator-preserving group had a smaller flap size (104.4 ± 84.3 cm2 versus 145.9 ± 94.1 cm2, p = 0.003), shorter reconstruction time (266.3 ± 76.1 min versus 302.0 ± 103.0 min, p = 0.013), and fewer donor-site complications (2.4% versus 13.3%, p = 0.009) than the traditional group, whereas the flap success rate was comparable (96.5% versus 96.4%) between them. Five cases received a second ALT flap from the same donor site after 3 failures and 2 metachronous defects. CONCLUSIONS: Multiple perforators in ALT flaps allow the harvesting of 2 ALT flaps from the same donor-site metachronously. Our classification and applications can improve efficiency while reducing donor-site morbidity.


Asunto(s)
Colgajo Perforante , Procedimientos de Cirugía Plástica , Humanos , Muslo/cirugía , Muslo/irrigación sanguínea , Colgajos Quirúrgicos/cirugía , Colgajo Perforante/irrigación sanguínea
9.
Small ; : e2307910, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38072788

RESUMEN

To investigate synergistic effect between geometric and electronic structures on directing CO2 RR selectivity, water phase synthetic protocol and surface architecture engineering strategy are developed to construct monodispersed Bi-doped Cu-based nanocatalysts. The strongly correlated catalytic directionality and Bi3+ dopant can be rationalized by the regulation of [*COOH]/[*CO] adsorption capacities through the appropriate doping of Bi3+ electronic modulator, resulting in volcano relationship between FECO /TOFCO and surface EVBM values. Spectroscopic study reveals that the dual-site binding mode ([Cu─µâ”€C(═O)O─Bi3+ ]) enabled by Cu1 Bi3+ 2 motif in single-phase Cu150 Bi1 nanocatalyst drives CO2-to-CO conversion. In contrast, the study of dynamic Bi speciation and phase transformation in dual-phase Cu50 Bi1 nanocatalyst unveils that the Bi0 -Bi0 contribution emerges at the expense of BOC phase, suggesting metallic Bi0 phase acting as [H]˙ formation center switches CO2 RR selectivity toward CO2-to-HCOO- conversion via [*OCHO] and [*OCHOK] intermediates. This work provides significant insight into how geometric architecture cooperates with electronic effect and catalytic motif/phase to guide the selectivity of electrocatalytic CO2 reduction through the distinct surface-bound intermediates and presents molecular-level understanding of catalytic mechanism for CO/HCOO- formation.

10.
Small ; : e2307180, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054789

RESUMEN

Despite the unique advantages of single-atom catalysts, molecular dual-active sites facilitate the C-C coupling reaction for C2 products toward the CO2 reduction reaction (CO2 RR). The Ni/Cu proximal dual-active site catalyst (Ni/Cu-PASC) is developed, which is a harmonic catalyst with dual-active sites, by simply mixing commercial Ni-phthalocyanine (Ni-Pc) and Cu-phthalocyanine (Cu-Pc) molecules physically. According to scanning transmission electron microscopy (STEM) and transmission electron microscopy (TEM) energy dispersive spectroscopy (EDS) data, Ni and Cu atoms are separated, creating dual-active sites for the CO2 RR. The Ni/Cu-PASC generates ethanol with an FE of 55%. Conversely, Ni-Pc and Cu-Pc have only detected single-carbon products like CO and HCOO- . In situ X-ray absorption spectroscopy (XAS) indicates that CO generation is caused by the stable Ni active site's balanced electronic state. The CO production from Ni-Pc consistently increased the CO concentration over Cu sites attributed to subsequent reduction reaction through a C-C coupling on nearby Cu. The CO bound (HCOO- ) peak, which can be found on Cu-Pc, vanishes on Ni/Cu-PASC, as shown by in situ fourier transformation infrared (FTIR). The characteristic intermediate of *CHO instead of HCOO- proves to be the prerequisite for multi-carbon products by electrochemical CO2 RR. The work demonstrates that the harmonic dual-active sites in Ni/Cu-PASC can be readily available by the cascading proximal active Ni- and Cu-Pc sites.

12.
Plast Reconstr Surg Glob Open ; 11(9): e5278, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37744772

RESUMEN

In the realm of oncologic reconstructive surgery, local or distant autologous tissue is frequently used to improve function and appearance. Due to advances in microsurgery and intensive care, reconstructive free flap surgery has become the standard treatment for head and neck cancer. However, the complexity of interdisciplinary intervention and prolonged surgical time inevitably increase the risk of cross-contamination, potentially leading to donor site metastasis. According to the literature, tumor transmission to the donor site of free flaps is extremely rare. We present the case of a 54-year-old man with left tongue squamous cell carcinoma. Three months after tumor ablation and reconstruction with a free anterolateral thigh flap, the patient presented with a mass on the donor site of the left thigh, which was proven to be a metastasis. A systemic workup revealed multiple metastases. Six months after reconstruction, the patient died of COVID-19 pneumonia. The incidence and risk factors of donor site metastasis are not well known. The primary causes are direct implantation or hematogenous spread. Cross-contamination is primarily prevented by the surgeon's awareness and avoidance. The development of new-onset lesions at the donor site warrants additional testing to detect systemic disease progression during follow-up.

13.
J Plast Reconstr Aesthet Surg ; 86: 199-204, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37748377

RESUMEN

BACKGROUND: The fibula flap has been the workhorse flap for mandibular reconstruction. However, relationships among the bone, skin, and vessels raise concerns about donor-side selection. This study aimed to clarify its impact on clinical outcomes. METHODS: Between September 2013 and June 2021, 61 cases of fibula osteoseptocutaneous flaps for mandibular and intraoral reconstruction were categorized into the landing-down (N = 25) and swing-up (N = 36) groups depending on whether the skin was easily accessible within the oral cavity. The demographics, operative findings, and outcomes of the cases were compared. RESULTS: Overall, seven (11%) flaps developed skin necrosis, including four partial and three total necrosis. The skin necrosis rate was higher in the swing-up than in the landing-down group (19% vs. 0%, p = 0.035). CONCLUSIONS: When using the fibula osteoseptocutaneous flap for mandibular and intraoral reconstructions, ensuring that the skin is properly located within the oral cavity could reduce the risk of skin necrosis.


Asunto(s)
Neoplasias Mandibulares , Reconstrucción Mandibular , Humanos , Peroné , Colgajos Quirúrgicos , Mandíbula/cirugía , Piel , Necrosis , Neoplasias Mandibulares/cirugía , Trasplante Óseo
14.
J Plast Reconstr Aesthet Surg ; 85: 316-325, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37541048

RESUMEN

A leftover narrow strip of the posterior pharyngeal wall may form after laryngopharyngectomy, and whether to retain it during reconstruction remains debated owing to the differing views on the incidence of leakage and strictures. This study aimed to ascertain whether this remnant posterior pharyngeal wall is advantageous or disadvantageous to surgeons performing pharyngoesophageal reconstruction. We reviewed the data of patients with circumferential or near-circumferential pharyngoesophageal defects following oncological laryngopharyngectomy who underwent reconstructive surgery utilizing the anterolateral thigh flap. They were then categorized into two groups: circumferential and near-circumferential. Thereafter, their demographics, operative findings, and postoperative outcomes were compared. Forty patients (20 in each group) with an average age of 57.2 ± 6.7 years (range: 40-72) were enrolled in the study. All flaps except one survived. During a mean follow-up of 41.1 ± 24.6 (range: 6-95) months, the stricture rate was significantly lower in the near-circumferential group (one vs. nine [from 17 patients who had resumed oral intake postoperatively] patients in the near-circumferential and circumferential groups, respectively, p = 0.002). Oral intake was viable in all patients with near-circumferential defects but only in 11 patients with circumferential defects (p = 0.003). The near-circumferential group had fewer strictures and better tolerance of oral nutrition, supporting the incorporation of the residual posterior pharyngeal wall via near-circumferential reconstruction instead of discarding it to facilitate circumferential reconstruction.


Asunto(s)
Procedimientos de Cirugía Plástica , Humanos , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/efectos adversos , Muslo/cirugía , Constricción Patológica , Resultado del Tratamiento , Estudios Retrospectivos
15.
Plast Reconstr Surg Glob Open ; 11(8): e5182, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37577248

RESUMEN

Reconstructing a mangled limb is complex and requires expertise in both bone and soft-tissue reconstruction, particularly when there is significant muscle loss. Typically, multistage surgery is necessary, starting with soft-tissue coverage, followed by bone grafting and tendon transfers. Sometimes, microsurgical techniques such as vascularized bone grafts and free functional muscle transfers are necessary, especially when there is a bone defect of over 6 cm; the soft-tissue environment is infected, scarred, or poorly vascularized; or there are extensive musculotendinous injuries. We treated a 34-year-old man who had a crushed left forearm resulting in an 18 × 8 cm open wound, 5-cm radius and 7-cm ulna bone defects, loss of the extensor pollicis longus and brevis muscles, and extensive injuries to the other musculotendinous structures of the forearm. To accomplish a one-stage reconstruction, we used a chimeric fibula osteomyocutaneous flap that included a 20 × 10 cm skin flap, peroneus brevis muscle with its motor nerve, and two segments of fibula. The proximal and distal fibula segments were used for ulnar and radial bone reconstruction, respectively, preserving forearm supination and pronation. The peroneus brevis tendon was sutured to the extensor pollicis longus tendon, and its motor nerve was coaptated with the posterior interosseous nerve to restore thumb extension. The skin flap provided complete coverage of all exposed bone and tendon structures. At the 12-month follow-up, the patient regained full extension of the thumb, and there were no difficulties with forearm supination and pronation or with foot eversion and plantar flexion at the donor leg.

16.
iScience ; 26(7): 107202, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37485375

RESUMEN

We sought to study the role of circulating cellular clusters (CCC) -such as circulating leukocyte clusters (CLCs), platelet-leukocyte aggregates (PLA), and platelet-erythrocyte aggregates (PEA)- in the immunothrombotic state induced by COVID-19. Forty-six blood samples from 37 COVID-19 patients and 12 samples from healthy controls were analyzed with imaging flow cytometry. Patients with COVID-19 had significantly higher levels of PEAs (p value<0.001) and PLAs (p value = 0.015) compared to healthy controls. Among COVID-19 patients, CLCs were correlated with thrombotic complications (p value = 0.016), vasopressor need (p value = 0.033), acute kidney injury (p value = 0.027), and pneumonia (p value = 0.036), whereas PEAs were associated with positive bacterial cultures (p value = 0.033). In predictive in silico simulations, CLCs were more likely to result in microcirculatory obstruction at low flow velocities (≤1 mm/s) and at higher branching angles. Further studies on the cellular component of hyperinflammatory prothrombotic states may lead to the identification of novel biomarkers and drug targets for inflammation-related thrombosis.

17.
Sci Rep ; 13(1): 11135, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37429950

RESUMEN

Graph theory can be used to address problems with complex network structures. Congenital heart diseases (CHDs) involve complex abnormal connections between chambers, vessels, and organs. We proposed a new method to represent CHDs based on graph theory, wherein vertices were defined as the spaces through which blood flows and edges were defined by the blood flow between the spaces and direction of the blood flow. The CHDs of tetralogy of Fallot (TOF) and transposition of the great arteries (TGA) were selected as examples for constructing directed graphs and binary adjacency matrices. Patients with totally repaired TOF, surgically corrected d-TGA, and Fontan circulation undergoing four-dimensional (4D) flow magnetic resonance imaging (MRI) were included as examples for constructing the weighted adjacency matrices. The directed graphs and binary adjacency matrices of the normal heart, extreme TOF undergoing a right modified Blalock-Taussig shunt, and d-TGA with a ventricular septal defect were constructed. The weighted adjacency matrix of totally repaired TOF was constructed using the peak velocities obtained from 4D flow MRI. The developed method is promising for representing CHDs and may be helpful in developing artificial intelligence and conducting future research on CHD.


Asunto(s)
Cardiopatías Congénitas , Defectos del Tabique Interventricular , Tetralogía de Fallot , Transposición de los Grandes Vasos , Humanos , Inteligencia Artificial , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/cirugía , Tetralogía de Fallot/diagnóstico por imagen , Tetralogía de Fallot/cirugía
18.
Chemosphere ; 337: 139357, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37392801

RESUMEN

The 3-D matrix scale ion-exchange mechanism was explored for high-capacity cadmium (Cd) removal using bone chars (BC) chunks (1-2 mm) made at 500 °C (500BC) and 700 °C (700BC) in aqueous solutions. The Cd incorporation into the carbonated hydroxyapatite (CHAp) mineral of BC was examined using a set of synchrotron-based techniques. The Cd removal from solution and incorporation into mineral lattice were higher in 500BC than 700BC, and the diffusion depth was modulated by the initial Cd concentration and charring temperature. A higher carbonate level of BC, more pre-leached Ca sites, and external phosphorus input enhanced Cd removal. The 500BC showed a higher CO32-/PO43- ratio and specific surface area (SSA) than the 700BC, providing more vacant sites by dissolution of Ca2+. In situ observations revealed the refilling of sub-micron pore space in the mineral matrix because of Cd incorporation.The X-ray nanodiffraction (XND) analyses revealed that Cd was mainly removed from water by incorporation into the mineral lattice of 500BC via ion exchange, rather than surface sorption and precipitation, and the mineral phase was transformed from hydroxyapatite (HAp) to cadmium hydroxyapatite (Cd-HAp). The Rietveld's refinement of X-ray diffraction (XRD) data resolved up to 91% of the crystal displacement of Ca2+ by Cd2+. The specific phase and stoichiometry of the new Cd-HAp mineral was dependent on the level of ion exchange. This mechanistic study confirmed that 3-D ion exchange was the most important path for heavy metal removal from aqueous solution and immobilization in BC mineral matrix, and put forward a novel and sustainable remediation strategy for Cd removal in wastewater and soil clean-up.


Asunto(s)
Cadmio , Durapatita , Durapatita/química , Cadmio/química , Fósforo , Adsorción
19.
ACS Nano ; 17(11): 10181-10190, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37212535

RESUMEN

Modern infrared (IR) microscopy, communication, and sensing systems demand control of the spectral characteristics and polarization states of light. Typically, these systems require the cascading of multiple filters, polarization optics, and rotating components to manipulate light, inevitably increasing their sizes and complexities. Here, we report two-terminal mid-infrared (mid-IR) emitters, in which tuning the polarity of the applied bias can switch their emission peak wavelengths and linear polarization states along two orthogonal orientations. Our devices are composed of two back-to-back p-n junctions formed by stacking anisotropic light-emitting materials, black phosphorus and black arsenic-phosphorus with MoS2. By controlling the crystallographic orientations and engineering the band profile of heterostructures, the emissions of two junctions exhibit distinct spectral ranges and polarization directions; more importantly, these two electroluminescence (EL) units can be independently activated, depending on the polarity of the applied bias. Furthermore, we show that when operating our emitter under the polarity-switched pulse mode, the time-averaged EL exhibits the characteristics of broad spectral coverage, encompassing the entire first mid-IR atmospheric window (λ: 3-5 µm), and electrically tunable spectral shapes.

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