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1.
Nature ; 593(7857): 61-66, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33953410

RESUMEN

In only a few decades, lithium-ion batteries have revolutionized technologies, enabling the proliferation of portable devices and electric vehicles1, with substantial benefits for society. However, the rapid growth in technology has highlighted the ethical and environmental challenges of mining lithium, cobalt and other mineral ore resources, and the issues associated with the safe usage and non-hazardous disposal of batteries2. Only a small fraction of lithium-ion batteries are recycled, further exacerbating global material supply of strategic elements3-5. A potential alternative is to use organic-based redox-active materials6-8 to develop rechargeable batteries that originate from ethically sourced, sustainable materials and enable on-demand deconstruction and reconstruction. Making such batteries is challenging because the active materials must be stable during operation but degradable at end of life. Further, the degradation products should be either environmentally benign or recyclable for reconstruction into a new battery. Here we demonstrate a metal-free, polypeptide-based battery, in which viologens and nitroxide radicals are incorporated as redox-active groups along polypeptide backbones to function as anode and cathode materials, respectively. These redox-active polypeptides perform as active materials that are stable during battery operation and subsequently degrade on demand in acidic conditions to generate amino acids, other building blocks and degradation products. Such a polypeptide-based battery is a first step to addressing the need for alternative chemistries for green and sustainable batteries in a future circular economy.


Asunto(s)
Suministros de Energía Eléctrica , Electroquímica , Péptidos/química , Animales , Bovinos , Línea Celular , Supervivencia Celular , Óxidos N-Cíclicos/química , Ratones , Osteoblastos/citología , Oxidación-Reducción , Péptidos/síntesis química , Desarrollo Sostenible , Viológenos/química
2.
Nature ; 591(7848): 54-60, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658692

RESUMEN

Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms1,2. Present-day photonic quantum computers3-7 have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware-software system for executing many-photon quantum circuit operations using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. The system enables remote users to execute quantum algorithms that require up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and photon number-resolving readout on all outputs. Detection of multi-photon events with photon numbers and rates exceeding any previous programmable quantum optical demonstration is made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra and graph similarity8. These demonstrations validate the platform as a launchpad for scaling photonic technologies for quantum information processing.

3.
Phys Chem Chem Phys ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324950

RESUMEN

In this study, Eu3+ ion singly doped and Eu3+/Sm3+ ions co-doped ZnS semiconductor quantum dots (QDs) were successfully synthesized using a wet chemical method in 1-octadecene (ODE) solvent. The successful doping of Sm3+ and Eu3+ ions into the ZnS host lattice and the composition and valence of the elements present in the sample were confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Structural and morphological studies revealed the presence of Eu3+-doped ZnS and Eu3+/Sm3+ co-doped ZnS QDs of about 3-4 nm size with a zinc blende structure. The Judd-Ofelt (J-O) intensity parameters of Eu3+-doped ZnS QDs were determined from their fluorescence spectra. The optical properties of Eu3+/Sm3+ co-doped ZnS QDs were studied by changing the Eu3+ ion concentration and fixing the Sm3+ ion concentration. The photoluminescence (PL) spectra of Eu3+/Sm3+ co-doped ZnS QDs were obtained at an excitation wavelength of 403 nm (6H5/2 → 6P3/2 transition of Sm3+ ions) in the 525-725 nm range. The effective energy transfer (ET) process from Sm3+ to Eu3+ ions was confirmed and explained in detail using the Reisfeld approximation and the Inokuti-Hirayama model. The CIE color coordinates of the Eu3+/Sm3+ co-doped ZnS QDs were obtained using PL spectral data. Eu3+/Sm3+ co-doped ZnS QDs exhibited a long lifetime and emitted warm red light. These interesting properties give Eu3+/Sm3+ co-doped ZnS QDs great potential for applications in photovoltaics, photocatalysis, and biomarkers.

4.
Zhonghua Yi Xue Za Zhi ; 104(13): 1057-1063, 2024 Apr 02.
Artículo en Zh | MEDLINE | ID: mdl-38561301

RESUMEN

Objective: To investigate the effect of deep neuromuscular blockade (DNMB) combined with low pneumoperitoneum pressure anesthesia strategy on postoperative pain in patients undergoing laparoscopic colorectal surgery. Methods: This study was a randomized controlled trial. One hundred and twenty patients who underwent laparoscopic colorectal surgery at Cancer Hospital of Chinese Academy of Medical Sciences from December 1, 2022 to May 31, 2023 were selected and randomly divided into two groups by random number table method. Moderate neuromuscular blockade [train of four stimulations count (TOFC)=1-2] was maintained in patients of the control group (group C, n=60) and pneumoperitoneum pressure level was set at 15 mmHg(1 mmHg=0.133 kPa). DNMB [post-tonic stimulation count (PTC)=1-2] was maintained in patients of the DNMB combined with low pneumoperitoneum pressuregroup (group D, n=60) and pneumoperitoneum pressure level was set at 10 mmHg. The primary measurement was incidence of moderate to severe pain at 1 h after surgery. The secondary measurements the included incidence of moderate to severe pain at 1, 2, 3, 5 d and 3 months after surgery, the incidence of rescue analgesic drug use, the doses of sufentanil in analgesic pumps, surgical rating scale (SRS) score, the incidence of postoperative residual neuromuscular block, postoperative recovery [evaluated with length of post anesthesia care unit (PACU) stay, time of first exhaust and defecation after surgery and length of hospital stay] and postoperative inflammation conditions [evaluated with serum concentration of interleukin (IL)-1ß and IL-6 at 1 d and 3 d after surgery]. Results: The incidence of moderate to severe pain in group D 1 h after surgery was 13.3% (8/60), lower than 30.0% (18/60) of group C (P<0.05). The incidence of rescue analgesia in group D at 1 h and 1 d after surgery were 13.3% (8/60) and 4.2% (5/120), respectively, lower than 30.0% (18/60) and 12.5% (15/120) of group C (both P<0.05). The IL-1ß level in group D was (4.1±1.8)ng/L at 1 d after surgery, which was lower than (4.9±2.6) ng/L of group C (P=0.048). The IL-6 level in group D was (2.0±0.7)ng/L at 3 d after surgery, which was lower than (2.4±1.1) ng/L of group C (P=0.018). There was no significant difference in the doses of sufentanil in analgesic pumps, intraoperative SRS score, incidence of neuromuscular block residue, time spent in PACU, time of first exhaust and defecation after surgery, incidence of nausea and vomiting, and length of hospitalization between the two groups (all P>0.05). Conclusion: DNMB combined with low pneumoperitoneum pressure anesthesia strategy alleviates the early-stage pain in patients after laparoscopic colorectal surgery.


Asunto(s)
Alquenos , Cirugía Colorrectal , Laparoscopía , Bloqueo Neuromuscular , Nitrocompuestos , Neumoperitoneo , Humanos , Bloqueo Neuromuscular/métodos , Sufentanilo , Cirugía Colorrectal/métodos , Interleucina-6 , Laparoscopía/métodos , Dolor Postoperatorio , Analgésicos
5.
Histopathology ; 82(4): 508-520, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36221864

RESUMEN

Squamous cell carcinoma (SCC) is the most common malignant tumour of the penis. The 2022 WHO classification reinforces the 2016 classification and subclassifies precursor lesions and tumours into human papillomavirus (HPV)-associated and HPV-independent types. HPV-associated penile intraepithelial neoplasia (PeIN) is a precursor lesion of invasive HPV- associated SCC, whereas differentiated PeIN is a precursor lesion of HPV-independent SCC. Block-type positivity of p16 immunohistochemistry is the most practical daily utilised method to separate HPVassociated from HPVindependent penile SCC. If this is not feasible, the term SCC, not otherwise specified (NOS) is appropriate. Certain histologies that were previously classified as "subtypes" are now grouped, and coalesced as "patterns", under the rubric of usual type SCC and verrucous carcinoma (e.g. usual-type SCC includes pseudohyperplastic and acantholytic/pseudoglandular carcinoma, and carcinoma cuniculatum is included as a pattern of verrucous carcinoma). If there is an additional component of the usual type of invasive SCC (formerly termed hybrid histology), the tumour would be a mixed carcinoma (e.g. carcinoma cuniculatum or verrucous carcinoma with usual invasive SCC); in such cases, reporting of the relative percentages in mixed tumours may be useful. The consistent use of uniform nomenclature and reporting of percentages will inform the refinement of future reporting classification schemes and guidelines/recommendations. The classification of scrotal tumours is provided for the first time in the fifth edition of the WHO Blue book, and it follows the schema of penile cancer classification for both precursor lesions and the common SCC of the scrotum. Basal cell carcinoma of the scrotum may have a variable clinical course and finds a separate mention.


Asunto(s)
Carcinoma de Células Escamosas , Carcinoma Verrugoso , Neoplasias de los Genitales Masculinos , Infecciones por Papillomavirus , Neoplasias del Pene , Neoplasias Cutáneas , Masculino , Humanos , Infecciones por Papillomavirus/patología , Escroto/metabolismo , Escroto/patología , Carcinoma de Células Escamosas/patología , Neoplasias del Pene/patología , Virus del Papiloma Humano , Organización Mundial de la Salud , Papillomaviridae
6.
Surgeon ; 21(4): 256-262, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35989215

RESUMEN

OBJECTIVES: The aim of the study was to describe injuries related to electric scooter at a Major-Trauma-Centre in the UK, We reviewed data from January 2020-December 2020. METHODS: All patient-records mentioning electric-scooter at a major-MTC. Records were reviewed, and data were stratified according to two groups: electric scooter riders and other road users. A predefined survey was completed in all cases where 'e-scooter or electric scooter' was present. This contained variables such as patient demographics, mechanism of injury (including head and body protection), acuity, intoxication, treatment facility and clinical utilisation. Among incidents involving electric scooters, summary statistics on continuous and categorical variables of interest were reported. Healthcare modelling utilising time driven activity-based costing and Patient-Level-Activity-Costing used to conduct a post hoc analysis of health provider costs. RESULTS: 202 e-scooter injuries were identified. Riders were more likely to be young males aged 18-35, a minority of reported cases being associated with the influence of alcohol or drugs (7.4%). They fall independently involving no other party (87%); sustaining both minor and major injuries; with a significant proportion requiring urgent and emergent surgery 23.7% (n = 40) with 60.1% (n = 121) requiring further secondary care follow-up; whilst 16% require immediate admission with a mean LOS of 5.9 days, including 8-ITU admissions. The overall mortality rate was 0.5% (n = 1), and cost per patient was £1482.46/patient, reducing to £927.25/patient if immediate surgery (<12 h s) was not required. CONCLUSION: Due to an emphasis on social distancing, changes in UK law, e-scooters injuries have increased. Most injuries are reported in riders, and are minor, however the mean health episode cost was over £1000.00/patient due to the minority of serious injuries. Research on interventions to prevent e-scooter injuries including protective clothing like helmet wearing is needed to address this growing area of concern, and unnecessary costly healthcare utilisation.


Asunto(s)
Pandemias , Centros Traumatológicos , Masculino , Humanos , Estudios Retrospectivos , Estudios de Cohortes , Reino Unido/epidemiología , Accidentes de Tránsito
7.
Med J Malaysia ; 78(7): 907-913, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38159927

RESUMEN

INTRODUCTION: This study aimed to determine the prevalence and association between the severity of COVID-19 and short and long-term neuropsychiatric symptoms, as well as the risk factors for the development of these symptoms. MATERIALS AND METHODS: A prospective observational study was conducted between 1st October 2021 till September 2022 in the state of Johor, Malaysia. 300 patients with confirmed SARS-CoV-2 infection were randomly selected and followed up for six months. Data were analysed by using Chi-square test, Fisher's Exact test, Paired t test and Multiple logistic regression. RESULTS: The prevalence of short-term neuropsychiatric symptoms was 78%, with anosmia being the most prevalent symptom. Long-term symptoms were found in 22.75% of patients, with headache being the most prevalent (p= 0.001). COVID-19 Stage 2 and 3 infections were associated with a higher risk of short-term neuropsychiatric symptoms, OR for Stage 2 infection was 5.18 (95% CI: 1.48-16.97; p=0.009) and for Stage 3 infection was 4.52 (95% CI: 1.76-11.59; p=0.002). Complete vaccination was a significant predictor of longterm symptoms with adjusted OR 3.65 (95% CI 1.22-10.91; p=0.021). CONCLUSION: This study demonstrated that neuropsychiatric symptoms were common among COVID-19 patients in Johor, Malaysia and the risk of these symptoms was associated with the severity of the infection. Additionally, complete vaccination does not completely protect against long-term neuropsychiatric deficits. This is crucial for continuous monitoring and addressing neuropsychiatric symptoms in COVID-19 survivors.


Asunto(s)
COVID-19 , Pacientes Internos , Humanos , Anosmia , COVID-19/complicaciones , COVID-19/epidemiología , Malasia/epidemiología , SARS-CoV-2 , Estudios Prospectivos
8.
Phys Chem Chem Phys ; 23(28): 15257-15267, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34236363

RESUMEN

Tb3+-Doped ZnSe quantum dots (QDs) with a Tb content in the range of 0.5-7% were successfully synthesized by a wet chemical method. X-Ray diffraction (XRD) and transmission electron microscopy (TEM) analyses revealed that the as-synthesized QDs had a zinc blende (ZB) structure with a particle size of approximately 4 nm. The effect of Tb-doping on the structure and optical properties of the ZnSe QDs was studied. The emission spectra and photoluminescence (PL) decay kinetics data confirmed the successful incorporation of Tb3+ ions into the ZnSe host. The PL spectra also revealed that the intensity of dopant emission was significantly enhanced owing to the energy transfer (ET) from the host emission. The efficiency of the ET process from the ZnSe host to Tb3+ ions and between Tb3+ ions and the nature of these interaction mechanisms were determined by applying the Inokuti-Hirayama and Reisfeld models. The features of the ligand field and the optical properties of Tb3+ ions in the ZnSe QDs were studied using Judd-Ofelt theory. The dependence of the chromaticity features of ZnSe:Tb3+ QDs on the Tb concentration was estimated by the chromaticity coordinates and correlated color temperature (CCT). The Tb3+-doped ZnSe QDs with visible, tunable, and very long lifetime emission have potential for practical applications such as biological labeling, photocatalysis, and white-LED devices.

9.
Hong Kong Med J ; 27(5): 338-349, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34706984

RESUMEN

INTRODUCTION: Cycling is associated with a greater risk of traumatic brain injury (TBI) than other recreational activities. This study aimed to investigate the epidemiology of sports-related TBI in Hong Kong and to examine predictors for recreational cycling-induced intracranial haemorrhage. METHODS: This retrospective multicentre study included patients diagnosed with sports-related TBI in public hospitals in Hong Kong from 2015 to 2019. Computed tomography scans were reviewed by an independent assessor. The primary endpoint was traumatic intracranial haemorrhage. The secondary endpoint was an unfavourable Glasgow Outcome Scale (GOS) score at discharge from hospital. RESULTS: In total, 720 patients were hospitalised with sports-related TBI. The most common sport was cycling (59.2%). The crude incidence of cycling-related TBI was 1.1 per 100 000 population. Cyclists were more likely to exhibit intracranial haemorrhage and an unfavourable GOS score, compared with patients who had TBI because of other sports. Although 47% of cyclists had intracranial haemorrhage, only 15% wore a helmet. In multivariate analysis, significant predictors for intracranial haemorrhage were age ≥60 years, antiplatelet medication, moderate or severe TBI, and skull fracture. Among 426 cyclists, 375 (88%) had mild TBI, and helmet wearing was protective against intracranial haemorrhage, regardless of age, antiplatelet medication intake, and mechanism of injury. Of 426 cyclists, 31 (7.3%) had unfavourable outcomes on discharge from hospital. CONCLUSIONS: The incidence of sports-related TBI is low in Hong Kong. Although cycling-related head injuries carried greater risks of intracranial haemorrhage and unfavourable outcomes compared with other sports, most cyclists experienced good recovery. Helmet wearing among recreational cyclists with mild TBI was protective against intracranial haemorrhage and skull fracture.


Asunto(s)
Traumatismos en Atletas , Lesiones Traumáticas del Encéfalo , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/epidemiología , Lesiones Traumáticas del Encéfalo/etiología , Dispositivos de Protección de la Cabeza , Hong Kong/epidemiología , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
10.
Zhonghua Yi Xue Za Zhi ; 101(15): 1088-1092, 2021 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-33878837

RESUMEN

Objective: To investigate the general situation, detection range, testing reagents, and clinical performance of non-invasive prenatal testing (NIPT) for fetal chromosomal copy number variations (CNVs) in Chinese laboratories. Methods: The National Center for Clinical Laboratories of the National Health Commission designed a questionnaire for the detection of CNVs by NIPT, which included the investigation of whether the laboratory has carried out NIPT to detect CNVs and its testing scope, reagents/platforms, intended uses, screening populations and clinical performance. The questionnaires were distributed to 355 laboratories in 31 provinces, autonomous regions, and municipalities across the country on October, 2020. Further, the feedbacks were statistical analyzed. Results: Two hundred and twenty-eight laboratories had performed NIPT to detect CNVs, including 116 types of CNVs, and more than 95% of laboratories chose to detect the CNVs of 5p15 deletion, 22q11.2 deletion, 1p36 deletion, and 15q11.2 deletion. All testing reagents used were laboratory-developed tests and were based on massive parallel sequencing, the minimum amount of sequencing data was 3-15 M reads, the detection limit of fetal fraction was 3%-5%, and the minimum size of variants that can be detected was 1-5 Mb. The proportion of laboratories that apply CNVs testing for daily project, voluntary requirements of patients, and scientific research were 58.8% (134/228), 57.5% (131/228), and 20.6% (47/228), respectively. One hundred and thirty-four laboratories were fully or partially aware of the clinical performance of NIPT to detect microdeletion/microduplication syndromes, and the laboratories' declared sensitivity of NIPT for Cri du Chat syndrome, 22q11.2 deletion syndrome, 1p36 deletion syndrome, and Angelman syndrome were 50.0%-100%, 60.0%-100%, 50.0%-100%, and 33.3%-100%, and the positive predictive values were 9.0%-50.0%, 18.0%-100%, 20.0%-30.0%, and 20.0%. Conclusion: The detection of CNVs by NIPT in Chinese laboratories need to be standardized. Laboratories should detect CNVs with clear clinical significance in accordance with the guidelines, conduct performance validation of the reagents, then perform NIPT test and provide adequate interpretation after mastering the clinical performance sufficiently.


Asunto(s)
Trastornos de los Cromosomas , Pruebas Prenatales no Invasivas , China , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/genética , Variaciones en el Número de Copia de ADN , Femenino , Humanos , Laboratorios , Embarazo , Diagnóstico Prenatal
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