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3.
J Nutr Health Aging ; 28(5): 100202, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38460319

RESUMO

OBJECTIVES: The association between blood pressure and frailty outcome in the middle-aged and older population remains controversial. This study aimed to examine the relationship between trajectories of systolic blood pressure (SBP) and new-onset frailty. DESIGN: Cohort study with a 7-year follow-up. SETTING AND PARTICIPANTS: Data were derived from 4 waves (2011, 2013, 2015 and 2018) of the China Health and Retirement Longitudinal Study and 6168 participants aged ≥45 years were included in the study. METHODS: The frailty index (FI) was constructed based on 40 scored items, with FI ≥ 0.25 defined as frailty. We identified the 5-year trajectory of SBP by latent class trajectory modeling. The association between SBP trajectories and frailty was explored based on hazard ratios (HR) by four Cox proportional hazards models. Furthermore, we also investigated the relationship between mean SBP and systolic blood pressure variability (SBPV) and frailty. RESULTS: 6168 participants were included in this study with a mean age of 59 years. We identified five trajectories based on SBP, which are maintained low-stable SBP (T0), moderate-stable SBP (T1), remitting then increasing SBP (T2), increasing then remitting SBP (T3), and remaining stable at high SBP levels (T4). During the 7-year follow-up period, frailty outcome occurred in 1415 participants. After adjusting for other confounders, the two trajectories labeled "T2" and "T4" were associated with a higher risk of frailty compared with T0. In addition, elevated SBP and increased SBPV were associated with risk of frailty. CONCLUSIONS: Higher risk of frailty occurred in two trajectories, remitting then increasing and remaining stable at high SBP levels, were associated with a relatively higher risk of frailty.

4.
J Endocrinol Invest ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536656

RESUMO

PURPOSE: Primary aldosteronism (PA) diagnosis is affected by antihypertensive drugs that are commonly taken by patients with suspected PA. In this study, we developed and validated a diagnostic model for screening PA without drug washout. METHODS: We retrospectively analyzed 1095 patients diagnosed with PA or essential hypertension. Patients were randomly grouped into training and validation sets at a 7:3 ratio. Baseline characteristics, plasma aldosterone concentration (PAC), and direct renin concentration (DRC) before and after drug washout were separately recorded, and the aldosterone-to-renin ratio (ARR) was calculated. RESULTS: PAC and ARR were higher and direct renin concentration was lower in patients with PA than in patients with essential hypertension. Furthermore, the differences in blood potassium and sodium concentrations and hypertension grades between the two groups were significant. Using the abbreviations potassium (P), ARR (A), PAC (P), sodium (S), and hypertension grade 3 (3), the model was named PAPS3. The PAPS3 model had a maximum score of 10, with the cutoff value assigned as 5.5; it showed high sensitivity and specificity for screening PA in patients who exhibit difficulty in tolerating drug washout. CONCLUSION: PA screening remains crucial, and standard guidelines should be followed for patients to tolerate washout. The PAPS3 model offers an alternative to minimize risks and enhance diagnostic efficiency in PA for those facing washout challenges. Despite its high accuracy, further validation of this model is warranted through large-scale clinical studies.

5.
J Phys Chem A ; 128(12): 2330-2338, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38480504

RESUMO

An accurate, global, full-dimensional potential energy surface (PES) of NaCl + NaCl has been constructed by the fundamental invariant-neural network (FI-NN) fitting based on roughly 13,000 ab initio energies at the level of CCSD(T)-F12a/aug-cc-pVTZ, with the small fitting error of 0.16 meV. Extensive quasiclassical trajectory (QCT) calculations were performed on this PES to investigate the energy transfer process of the NaCl + NaCl collision at four different collision energies. Various quantities were obtained, including the cross-sections, energy transfer probability, average energy transfer, and collision lifetime. The probabilities of energy transfer (P(ΔE)) for prompt trajectories, nonreactive trajectories, and reactive trajectories deviate from a simple exponential decay pattern. Instead, a noteworthy probability is observed in the high-energy transfer region, indicative of supercollisions. The formation of the (NaCl)2 complex, coupled with a comparatively extended collision lifetime, promotes vibrational excitation in NaCl molecules. The reactive trajectories exhibit enhanced energy transfer, attributed to the longer lifetime of the NaCl dimer. This study not only provides an accurate and extensive understanding of the NaCl + NaCl collision dynamics but also reveals intriguing phenomena, such as supercollisions and enhanced energy transfer in reactive trajectories, shedding light on the complex intricacies of molecular interactions.

6.
Zhonghua Yi Xue Za Zhi ; 104(7): 499-506, 2024 Feb 20.
Artigo em Chinês | MEDLINE | ID: mdl-38317361

RESUMO

Objective: To analyze the efficacy and safety of first-line treatment with an anti-CD38 monoclonal antibody regimen for primary plasma cell leukemia (pPCL). Methods: Patients diagnosed with pPCL from December 1st, 2018 to July 26th, 2023, receiving first-line treatment of anti-CD38 monoclonal antibody-based regimens across multiple centers including Peking University People's Hospital, Fuxing Hospital of Capital Medical University, Qingdao Municipal Hospital, Shengjing Hospital of China Medical University, Handan Central Hospital, the First Affiliated Hospital of Harbin Medical University, the Fourth Hospital of Hebei Medical University and General Hospital of Ningxia Medical University were consecutively included. A total of 24 pPCL patients were included with thirteen being male and eleven being female. The median age [M(Q1, Q3)] was 60 (57, 70) years. Patients were grouped according to peripheral blood plasma cell (PBPC) percentage [5%-19% (n=14) vs ≥20% (n=10)]. Last follow-up date was September 26th, 2023. The median follow-up period was 9.1 (4.2, 15.5) months. Patients' data related with clinical baseline characteristics, efficacy, survival and safety were retrospectively collected. Cox proportional hazards regression model was used to analyze risk factors associated with survival. Results: Among 24 pPCL patients, 16 (66.7%) patients had anemia at diagnosis, 13(54.2%) patients had thrombocytopenia, 8 (33.3%) patients had a baseline estimated glomerular filtration rate (eGFR)<40 ml·min-1·(1.73m2)-1, 13 (54.2%) patients had elevated lactate dehydrogenase (LDH) levels. The median PBPC percentage was 16% (8%, 26%) . Fluorescence in situ hybridization testing indicated that patients harboring 17p deletion, t(4;14) or t(14;16) were 6 (25.0%), 4 (16.7%) and 4 (16.7%), respectively. The overall response rate was 83.3% (20/24). The median progression-free survival (PFS) was 20.5 (95%CI: 15.8-25.2) months, and the median overall survival (OS) was not reached. Estimated 1-year and 2-year PFS and OS rates were 75.0% and 89.1%, 37.5% and 53.4%, respectively. The median PFS and OS for patients with PBPC percentages 5%-19% and≥20% were not reached and 20.5 (95%CI:15.7-25.3) months, 17.8 months and not reached, respectively. There was no significant statistical difference of PFS and OS between two groups (all P>0.05). Multivariate Cox regression analysis showed that 1p32 deletion was the risk factor associated with PFS (HR=7.7, 95%CI: 1.1-54.9, P=0.043). Seventeen patients (70.8%) developed grade 3-4 hematologic toxicities. Twelve patients (50.0%) developed grade 3-4 thrombocytopenia. Sixteen patients (66.7%) developed infection. All hematologic toxicities and infections were improved after supportive treatment. Conclusion: First-line treatment with anti-CD38 monoclonal antibody-based therapy for pPCL is effective and safe.


Assuntos
Antineoplásicos , Leucemia Plasmocitária , Trombocitopenia , Feminino , Humanos , Masculino , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hibridização in Situ Fluorescente , Leucemia Plasmocitária/induzido quimicamente , Leucemia Plasmocitária/tratamento farmacológico , Estudos Retrospectivos , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Resultado do Tratamento , Pessoa de Meia-Idade , Idoso
7.
G3 (Bethesda) ; 14(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38366575

RESUMO

Reference genome assemblies have been created from multiple lineages within the Canidae family; however, despite its phylogenetic relevance as a basal genus within the clade, there is currently no reference genome for the gray fox (Urocyon cinereoargenteus). Here, we present a chromosome-level assembly for the gray fox (U. cinereoargenteus), which represents the most contiguous, non-domestic canid reference genome available to date, with 90% of the genome contained in just 34 scaffolds and a contig N50 and scaffold N50 of 59.4 and 72.9 Megabases, respectively. Repeat analyses identified an increased number of simple repeats relative to other canids. Based on mitochondrial DNA, our Vermont sample clusters with other gray fox samples from the northeastern United States and contains slightly lower levels of heterozygosity than gray foxes on the west coast of California. This new assembly lays the groundwork for future studies to describe past and present population dynamics, including the delineation of evolutionarily significant units of management relevance. Importantly, the phylogenetic position of Urocyon allows us to verify the loss of PRDM9 functionality in the basal canid lineage, confirming that pseudogenization occurred at least 10 million years ago.


Assuntos
Cromossomos , Raposas , Animais , Raposas/genética , Filogenia , Cromossomos/genética , DNA Mitocondrial/genética , Genoma
8.
J Phys Chem A ; 128(6): 1032-1040, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38315118

RESUMO

Previous experiments and theories have shown the existence of heavy-light-heavy (HLH) reactivity oscillation in the Cl + CH4 reaction and anticipated that similar oscillations should exist in many HLH reactions involving polyatomic reagents. However, the total reaction probabilities for the Cl + CHD3 → HCl + CD3 reaction exhibit only a step-like feature, and the total reaction probabilities for Cl + CHT3 → HCl + CT3 do not show any structure at all. Here, we report seven-dimensional state-to-state quantum dynamics studies for this reaction on the FI-NN PES, and we demonstrate that HLH reactivity oscillations also exist in these two reactions, manifesting as peaks in the reaction probabilities for low product rotational states. These oscillations, however, are obscured in the total reaction probability because of the higher excitation of j ≥ 2 product rotational states. Furthermore, the isotope replacement of nonreactive hydrogen with deuterium and tritium significantly enhances reactivity at collision energies above 0.112 eV, indicating an inverse secondary isotope effect on the probabilities, which is proved to be also caused by HLH mass combination. We also demonstrate that the highly rotational excitation of CHD3 substantially enhances reactivity and the HLH oscillations, similar to HLH triatomic reactions. These observations are completely different from those in the H + CHD3 reaction, which is also a late-barrier reaction. Therefore, the HLH mass combination is very important, which affects not only the reactivity oscillation but also the amplitude and product rotational state distribution and makes the initial rotation excitation play a pivotal role in the reaction.

9.
Zhonghua Yi Xue Za Zhi ; 104(9): 690-694, 2024 Mar 05.
Artigo em Chinês | MEDLINE | ID: mdl-38418168

RESUMO

Objective: To investigate the changes of spinal vascular blood flow in SD rats after cervical, thoracic and lumbar spinal cord injury (SCI) using super-resolution ultrafast ultrasound technology. Methods: A total of 9 SD rats were used to construct SCI models at different segments using a 50 g aneurysm clip. Super-resolution ultrafast ultrasound technology was used to perform vascular blood flow imaging on the spinal cord of rats before and after injury at 6 hours, obtaining quantitative information such as spinal cord vascular density and blood flow velocity. Results: Ultrasound imaging showed that after SCI, the vascular density in the thoracic segment decreased (18.16%±1.04%) more than in the cervical segment (11.42%±1.39%) and lumbar segment (13.88%±1.43%, both P<0.05). The length of the spinal cord with decreased vascular density in the thoracic segment [(4.80±0.34)mm] was longer than that in the cervical segment [(2.80±0.57)mm] and lumbar segment [(3.10±0.36)mm, both P<0.05]. After injury, the decrease of blood flow in the thoracic segment [(8.87±0.85)ml/min] was higher than that in the cervical segment [(4.88±0.56)ml/min] and lumbar segment [(6.19±0.71)ml/min, both P<0.05]. HE staining and Nissl staining showed that the proportion of cavity area after thoracic SCI (11.53%±0.93%) was higher than that in the cervical segment (4.90%±1.72%) and lumbar segment (7.64%±0.84%, both P<0.05). The number of Nissl bodies in the thoracic segment (18.0±5.3) was also lower than that in the cervical segment (32.3±5.1) and lumbar segment (37.0±5.6) (both P<0.05). Conclusions: There are different changes in vascular blood flow after SCI in different segments of rats. The same injury causes the most severe damage to blood vessels in the thoracic spinal cord, followed by the lumbar spinal cord, and the cervical spinal cord has the least damage.


Assuntos
Medula Cervical , Traumatismos da Medula Espinal , Ratos , Animais , Ratos Sprague-Dawley , Medula Espinal/irrigação sanguínea , Medula Espinal/diagnóstico por imagem , Ultrassonografia
10.
Microb Ecol ; 87(1): 46, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407587

RESUMO

Bacterial symbionts are crucial to the biology of Bactrocera dorsalis. With larval diet (fruit host) being a key factor that determines microbiome composition and with B. dorsalis using more than 400 fruits as hosts, it is unclear if certain bacterial symbionts are preserved and are passed on to B. dorsalis progenies despite changes in larval diet. Here, we conducted a fly rearing experiment to characterize diet-induced changes in the microbiome of female B. dorsalis. In order to explicitly investigate the impacts of larval diet on the microbiome, including potential stable bacterial constituents of B. dorsalis, we performed 16S rRNA sequencing on the gut tissues of teneral female flies reared from four different host fruits (guava, mango, papaya, and rose apple) infested using a single cohort of wild B. dorsalis that emerged from tropical almond (mother flies). Although B. dorsalis-associated microbiota were predominantly shaped by the larval diet, some major bacterial species from the mother flies were retained in progenies raised on different larval diets. With some variation, Klebsiella (ASV 1 and 2), Morganella (ASV 3), and Providencia (ASV 6) were the major bacterial symbionts that were stable and made up 0.1-80% of the gut and ovipositor microbiome of female teneral flies reared on different host fruits. Our results suggest that certain groups of bacteria are stably associated with female B. dorsalis across larval diets. These findings provide a basis for unexplored research on symbiotic bacterial function in B. dorsalis and may aid in the development of novel management techniques against this devastating pest of horticultural importance.


Assuntos
Frutas , Tephritidae , Humanos , Feminino , Animais , Larva , RNA Ribossômico 16S/genética
11.
Nat Commun ; 15(1): 1698, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402199

RESUMO

Quantum interference between reaction pathways around a conical intersection (CI) is an ultrasensitive probe of detailed chemical reaction dynamics. Yet, for the hydrogen exchange reaction, the difference between contributions of the two reaction pathways increases substantially as the energy decreases, making the experimental observation of interference features at low energy exceedingly challenging. We report in this paper a combined experimental and theoretical study on the H + HD → H2 + D reaction at the collision energy of 1.72 eV. Although the roaming insertion pathway constitutes only a small fraction (0.088%) of the overall contribution, angular oscillatory patterns arising from the interference of reaction pathways were clearly observed in the backward scattering direction, providing direct evidence of the geometric phase effect at an energy of 0.81 eV below the CI. Furthermore, theoretical analysis reveals that the backward interference patterns are mainly contributed by two distinct groups of partial waves (J ~ 10 and J ~ 19). The well-separated partial waves and the geometric phase collectively influence the quantum reaction dynamics.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38285614

RESUMO

As a key molecular scaffold for various flavonoids, naringenin is a value-added chemical with broad pharmaceutical applicability. For efficient production of naringenin from acetate, it is crucial to precisely regulate the carbon flux of the oxaloacetate-phosphoenolpyruvate (OAA-PEP) regulatory node through appropriate pckA expression control, as excessive overexpression of pckA can cause extensive loss of OAA and metabolic imbalance. However, considering the critical impact of pckA on naringenin biosynthesis, the conventional strategy of transcriptional regulation of gene expression is limited in its ability to cover the large and balanced solution space. To overcome this hurdle, in this study, pckA expression was fine-tuned at both the transcriptional and translational levels in a combinatorial expression library for the precise exploration of optimal naringenin production from acetate. Additionally, we identified the effects of regulating pckA expression by validating the correlation between phosphoenolpyruvate kinase (PCK) activity and naringenin production. As a result, the flux-optimized strain exhibited a 49.8-fold increase compared with the unoptimized strain, producing 122.12 mg/L of naringenin. Collectively, this study demonstrated the significance of transcriptional and translational flux rebalancing at the key regulatory node, proposing a pivotal metabolic engineering strategy for the biosynthesis of various flavonoids derived from naringenin using acetate. ONE-SENTENCE SUMMARY: In this study, transcriptional and translational regulation of pckA expression at the crucial regulatory node was conducted to optimize naringenin biosynthesis using acetate in E. coli.


Assuntos
Escherichia coli , Flavanonas , Flavonoides , Escherichia coli/genética , Escherichia coli/metabolismo , Fosfoenolpiruvato/metabolismo , Flavonoides/metabolismo , Acetatos/metabolismo
13.
J Chem Phys ; 160(1)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38168693

RESUMO

The 6D time-dependent wave packet calculations were performed to explore H2 dissociation on Ag, Au, and two AgAu alloy surfaces, using four newly fitted potential energy surfaces based on the neural network fitting to density functional theory energy points. The ligand effect resulting from the Ag-Au interaction causes a reduction in the barrier height for H2+Ag/Au(111) compared to H2+Ag(111). However, the scenario is reversed for H2+Au/Ag(111) and H2+Au(111). The 6D dissociation probabilities of H2 on Ag/Au(111) surfaces are significantly higher than those on the pure Ag(111) surface, but the corresponding results for H2 on Au/Ag(111) surfaces are substantially lower than those on the pure Au(111) surface. The reactivity of H2 on Au(111) is larger than that on Ag(111), despite Ag(111) having a slightly lower static barrier height. This can be attributed to the exceptionally small dissociation probabilities at the hcp and fcc regions, which are at least 100 times smaller compared to those at the bridge or top site for H2+Ag(111). Due to the late barrier being more pronounced, the vibrational excitation of H2 on Ag(111) is more effective in promoting the reaction than on Au(111). Moreover, a high degree of alignment dependence is detected for the four reactions, where the H2 dissociation has the highest probability at the helicopter alignment, as opposed to the cartwheel alignment.

14.
J Prev Alzheimers Dis ; 11(1): 214-221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38230734

RESUMO

BACKGROUND: Alzheimer's disease (AD) and vascular cognitive impairment (VCI) are the two main causes of dementia. AD and VCI share similar symptoms of cognitive decline and may be attributable to similar risk factors. Establishing a prospective cohort to compare VCI and AD would help to understand vascular risk factors related to dementia. OBJECTIVES: China Alzheimer's disease and Neurodegenerative Disorder Research (CANDOR) study is a prospective multicenter cohort study. It aims to study the similarities and differences between AD and post stroke cognitive impairment (PSCI) in neuroimaging changes, disease progression, and multiple omics studies. DESIGN: This is an ongoing study. From July 31, 2019, to August 1, 2022, we recruited 1449 participants with ages between 40 and 100 years. The cohort included three groups: AD group, PSCI group, and normal cognitive (NC) group. Data were collected in face-to-face interviews at baseline, and will be followed up every year for 4 years. The PSCI group had additional follow-ups at 3-month and 6-month after enrollment. Brain Magnetic Resonance Imaging (MRI) included high-resolution sequences for intracranial arteries. Cognitive assessments and follow-up information will be prospectively collected. Biological specimens including blood and urine at baseline were collected and tested. PARTICIPANTS: The targeted sample size of PSCI group was 500, AD group with 600 and NC group with 2000. There were 1449 participants enrolled. Include 508 participants were in NC group, 387 in AD group and 554 in PSCI group. MEASUREMENTS: Demographics, clinical parameters, and medical examinations were collected and performed. Cognitive assessment was performed to assess all cognitive domains including memory, language, executive function, and orientation function. CONCLUSIONS: The CANDOR study is a prospective cohort study. Data from this cohort provide us an opportunity to investigate the contribution of vascular factors to dementia pathogenesis.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Acidente Vascular Cerebral , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Estudos Prospectivos , Estudos de Coortes , Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia
15.
Eur Rev Med Pharmacol Sci ; 28(1): 1-22, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235855

RESUMO

OBJECTIVE: Coronary artery disease (CAD) is a major global cause of death, greatly affecting life expectancy and quality of life for populations. With the advent of artificial intelligence (AI), there is new hope for accurately managing CAD. While recent studies have shown remarkable progress in AI and CAD research, there is a gap in comprehensive bibliometric analysis in this field. Therefore, this study aims to provide a thorough analysis of trends and hotspots in AI and CAD-related research utilizing bibliometrics. MATERIALS AND METHODS: Publications on AI and CAD relevant research from 2009 to 2023 were searched through the WoS core database (WoSCC). CiteSpace, VOSviewer and Excel 365 were used to conduct the bibliometric analysis. RESULTS: The bibliometric analysis included 1,248 publications, indicating a steady increase in AI and CAD-related publications annually. The United States of America (USA), China, and Germany were identified as the most influential countries in this field. Research institutions such as Cedars Sinai Med Ctr, Med Univ South Carolina, Harvard Med Sch and Capital Med Univ were the main contributors to research production. FRONT CARDIOVASC MED is the top-ranked journal, while J AM COLL CARDIOL emerged as the most cited journal. Schoepf, U. Joseph, Slomka, Piotr J., Berman, Daniel S. and Dey, Damini were the most prolific authors, while U. Rajendra Acharya was the most frequently co-cited author. Research related to the AI calculation of coronary flow reserve fraction and coronary artery calcification, based on coronary CT to identify CAD and cardiovascular risk, was a key research topic in this field. The potential link between cardiovascular risk stratification and radiomics is currently at the forefront of the field. CONCLUSIONS: This study is the first to use a bibliometric approach to visualize and analyze AI and CAD-related research. The findings provide insights into recent research trends and hotspots in the field and can serve as a reference for scholars to identify critical issues in this field.


Assuntos
Doença da Artéria Coronariana , Humanos , Inteligência Artificial , Qualidade de Vida , Bibliometria , China
16.
Insects ; 15(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38249030

RESUMO

Pineapple mealybug, Dysmicoccus brevipes (Hemiptera: Pseudococcidae), is a significant pest in pineapple production and a key trade barrier. We explored the potential use of ethyl formate (EF) as a methyl bromide alternative for the postharvest fumigation of D. brevipes in imported pineapples. When treated at 8 °C for 4 h, EF fumigation was effective against D. brevipes with LCt99, the lethal concentration × time product of EF necessary to achieve 99% mortality of D. brevipes nymphs and adults at 64.2 and 134.8 g h/m3, respectively. Sorption trials conducted with 70 g/m3 EF for 4 h at 8 °C using 7.5, 15 and 30% pineapple loading ratios (w/v) indicated that loading ratio lower than 30% is necessary to achieve the LCt99 values required to control D. brevipes. In a scaled up trial using 1 m3 chamber, EF fumigation with 70 g/m3 for 4 h at 8 °C with 20% pineapple loading ratio (w/v) resulted in a complete control of D. brevipes treated. There were no significant differences in hue values, sugar contents, firmness, and weight loss between EF-treated and untreated pineapples. Our results suggest that EF is a promising alternative to methyl bromide fumigation for the postharvest phytosanitary disinfection of D. brevipes in pineapples.

17.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38265082

RESUMO

Polanyi's rules predict that a late-barrier reaction yields vibrationally cold products; however, experimental studies showed that the H2 product from the late-barrier H + H2O(|04⟩-) and H + HOD(vOH = 4) reactions is vibrationally hot. Here, we report a potential-averaged five-dimensional state-to-state quantum dynamics study for the H + HOD(vOH = 0-4) → H2 + OD reactions on a highly accurate potential energy surface with the total angular momentum J = 0. It is found that with the HOD vibration excitation increasing from vOH = 1 to 4, the product H2 becomes increasingly vibrationally excited and manifests a typical characteristic of an early barrier reaction for vOH = 3 to 4. Analysis of the scattering wave functions revealed that vibrational excitation in the breaking OH bond moves the location of dynamical saddle point from product side to reactant side, transforming the reaction into an early barrier reaction. Interestingly, pronounced oscillatory structures in the total and product vibrational-state-resolved reaction probabilities were observed for the H + HOD(vOH = 3, 4) reactions, in particular at low collision energies, which originate from the Feshbach resonance states trapped in the bending/torsion excited vibrational adiabatic potential wells in the entrance region due to van der Waals interactions.

18.
Phys Chem Chem Phys ; 26(5): 4047-4051, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38224156

RESUMO

The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts.

19.
Zhonghua Yi Xue Za Zhi ; 103(45): 3608-3614, 2023 Dec 05.
Artigo em Chinês | MEDLINE | ID: mdl-38018059

RESUMO

The mutations of myeloproliferative neoplasma (MPN) mainly include driver mutations and non-driver mutations. The driver mutations mainly include JAK2 mutations, CALR mutations and MPL mutations and non-driver mutations mainly include ASXL1, DNMT3A, TET2, SF3B1, EZH2, TP53, SRSF2, USAF1, etc. Driver and non-driver mutations and their clonal evolution affect the thrombosis and disease transformation of MPN. Clonal hematopoiesis of MPN can occur decades before diagnosis, even in the fetal stage. After the emergence of clonal hematopoiesis, until the emergence and progression of MPN, gene mutation order, inflammation, interferon therapy affect the disease phenotype and clonal hematopoiesis of MPN. Although great progress has been made in the understanding of MPN clonal hematopoiesis and its evolution with the development of next-generation sequencing, there are still many limitations. In this study, we mainly discuss gene mutations of MPN and their influences on the thrombosis, leukemia and fibrosis transformation, and the influencing factors of clonal evolution, aiming to summarize the influence of clonal hematopoiesis and its evolution on the complications, prognosis and survival of MPN.


Assuntos
Leucemia , Transtornos Mieloproliferativos , Trombose , Humanos , Hematopoiese Clonal , Transtornos Mieloproliferativos/genética , Mutação , Janus Quinase 2/genética
20.
J Phys Chem A ; 127(45): 9513-9519, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37921345

RESUMO

We utilized the time-dependent wave packet approach to compute the first full-dimensional (6D) state-to-state differential cross sections (DCSs) for the title reaction with the initial nonrotating H2S in the ground and the (100) and (001) vibrational excited states. It is found that the fundamental symmetric and asymmetric stretching excitations of H2S exhibit almost the same influence on the DCS, but unlike the H + H2O → H2 + OH reaction, they greatly increase the vibrational excitation of both the H2 and SH products. The hot vibrational state distributions of H2 are consistent with the prediction of product energy disposal by Polanyi's rules for an early barrier reaction. Because the incident H atom reacts strongly with both the ground and excited S-H states, the large populations of product SH(v2 = 1), which are very close to the relative reactivity of the initial S-H(v = 0) state, can still be explained by the local mode picture for H2S and the nonreacting SH bond's spectator nature.

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