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Angewandte Chemie (International Ed. in... Jul 2024All-benzenoid polycyclic aromatic hydrocarbons or macrocycles usually display localized aromaticity. On the other hand, incorporation of quinoidal units into the...
All-benzenoid polycyclic aromatic hydrocarbons or macrocycles usually display localized aromaticity. On the other hand, incorporation of quinoidal units into the skeleton could lead to effective electron delocalization and global (anti)aromaticity. In this work, fully π-conjugated macrocycle 1 and bismacrocycle 2 containing both para-quinodimethane and triphenylamine units are efficiently synthesized mainly through intermolecular Friedel-Crafts alkylation reaction. They can be considered as a tetraazasuperbenzene and a hexaazasupernaphthalene, respectively, due to their similar geometry and electronic structures to the benzene and naphthalene. X-ray crystallographic analyses reveal a largely planar geometry for both 1 and 2 and variable-temperature NMR measurements disclose slow dynamic processes owing to restricted ring flipping of the phenyl rings. 1 and 2 can be easily oxidized into higher-oxidation-state species. NMR and theoretical calculations indicate that 12+ and 14+ show global anti-aromaticity and aromaticity, respectively, with a dominant 32π and 30π conjugation pathway, while for the bismacrocycle 2, its dication 22+, tetracation 24+ and hexacation 26+exhibit global aromaticity, antiaromaticity, and aromaticity with a 54π, 52π and 50π conjugation pathway along the outermost backbone, respectively.
PubMed: 38958027
DOI: 10.1002/anie.202407990 -
Nanotechnology Jul 2024This study employs cold-wall chemical vapor deposition to achieve the growth of MoTethin films on 4-inch sapphire substrates. A two-step growth process is utilized,...
This study employs cold-wall chemical vapor deposition to achieve the growth of MoTethin films on 4-inch sapphire substrates. A two-step growth process is utilized, incorporating MoOand Te powder sources under low-pressure conditions to synthesize MoTe2. The resultant MoTethin films exhibit a dominant 1T' phase, as evidenced by a prominent Raman peak at 161 cm. This preferential 1T' phase formation is attributed to controlled manipulation of the second-step growth temperature, essentially the reaction stage between Te vapor and the pre-deposited MoOx layer. Under these optimized growth conditions, the thickness of the continuous 1T'-MoTefilms can be precisely tailored within the range of 3.5 - 5.7 nm (equivalent to 5 - 8 layers), as determined by atomic force microscopy depth profiling. Hall-effect measurements unveil a typical hole concentration and mobility of 0.2 cm/V-s and 7.9 × 10cm, respectively, for the synthesized few-layered 1T'-MoTe2 films. Furthermore, Ti/Al bilayer metal contacts deposited on the few-layered 1T'-MoTefilms exhibit low specific contact resistances of approximately 1.0 × 10Ω-cmestimated by the transfer length model. This finding suggests a viable approach for achieving low ohmic contact resistance using the 1T'-MoTeintermediate layer between metallic electrodes and two-dimensional semiconductors.
PubMed: 38958023
DOI: 10.1088/1361-6528/ad5db7 -
Journal of Computational Biology : a... Jul 2024The estimation of haplotype structure and frequencies provides crucial information about the composition of genomes. Techniques, such as single-individual haplotyping,...
The estimation of haplotype structure and frequencies provides crucial information about the composition of genomes. Techniques, such as single-individual haplotyping, aim to reconstruct individual haplotypes from diploid genome sequencing data. However, our focus is distinct. We address the challenge of reconstructing haplotype structure and frequencies from pooled sequencing samples where multiple individuals are sequenced simultaneously. A frequentist method to address this issue has recently been proposed. In contrast to this and other methods that compute point estimates, our proposed Bayesian hierarchical model delivers a posterior that permits us to also quantify uncertainty. Since matching permutations in both haplotype structure and corresponding frequency matrix lead to the same reconstruction of their product, we introduce an order-preserving shrinkage prior that ensures identifiability with respect to permutations. For inference, we introduce a blocked Gibbs sampler that enforces the required constraints. In a simulation study, we assessed the performance of our method. Furthermore, by using our approach on two distinct sets of real data, we demonstrate that our Bayesian approach can reconstruct the dominant haplotypes in a challenging, high-dimensional set-up.
PubMed: 38957993
DOI: 10.1089/cmb.2023.0211 -
Frontiers in Genetics 2024Long QT syndrome (LQTS) is an autosomal dominant inherited cardiac condition characterized by a QT interval prolongation and risk of sudden death. There are 17 subtypes...
INTRODUCTION
Long QT syndrome (LQTS) is an autosomal dominant inherited cardiac condition characterized by a QT interval prolongation and risk of sudden death. There are 17 subtypes of this syndrome associated with genetic variants in 11 genes. The second most common is type 2, caused by a mutation in the gene, which is part of the potassium channel and influences the final repolarization of the ventricular action potential. This case report presents an Ecuadorian teen with congenital Long QT Syndrome type 2 (OMIM ID: 613688), from a family without cardiac diseases or sudden cardiac death backgrounds.
CASE PRESENTATION
A 14-year-old girl with syncope, normal echocardiogram, and an irregular electrocardiogram was diagnosed with LQTS. Moreover, by performing Next-Generation Sequencing, a pathogenic variant in the gene p.(Ala614Val) (ClinVar ID: VCV000029777.14) associated with LQTS type 2, and two variants of uncertain significance in the p.(Arg1654GlyfsTer23) (rs779447911), and p. (Arg34653Cys) (ClinVar ID: VCV001475968.4) genes were identified. Furthermore, ancestry analysis showed a mainly Native American proportion.
CONCLUSION
Based on the genomic results, the patient was identified to have a high-risk profile, and an implantable cardioverter defibrillator was selected as the best treatment option, highlighting the importance of including both the clinical and genomics aspects for an integral diagnosis.
PubMed: 38957812
DOI: 10.3389/fgene.2024.1395012 -
Plastic and Reconstructive Surgery.... Jul 2024Lipedema is the progressive symmetrical deposition of subcutaneous fat and fluid in the lower body, ordinarily sparing the trunk, upper limbs, face, and neck. It may... (Review)
Review
BACKGROUND
Lipedema is the progressive symmetrical deposition of subcutaneous fat and fluid in the lower body, ordinarily sparing the trunk, upper limbs, face, and neck. It may follow an autosomal dominant inheritance pattern. The gold standard treatment for lipedema is complete decongestive therapy, consisting of manual lymphatic drainage and compression garments. This scoping review assessed the existing literature on the effectiveness of liposuction as an alternative treatment for lipedema.
METHODS
A scoping review of electronically available literature within PubMed, Scopus, and Cochrane focused on liposuction as a treatment for lipedema considering the following inclusion criteria: human studies, case series of 10 or more, controlled trials, randomized controlled trials, patient-reported outcome measurement studies, survey analyses, descriptive studies, retrospective analyses, recurrence included, follow-up of 6 months or more, age 18 years or older, and treatment modality being liposuction.
RESULTS
Thirteen studies were selected. Nine studies reported decreased compression therapy use among patients following liposuction. No studies reported a long-term increase in compression therapy following liposuction. Studies found self-reported improvements in pain, mobility, bruising, and overall quality of life for patients following liposuction, many of whom had previously been on compressive therapy. Studies reported low rates of serious adverse events following liposuction, including deep vein thrombosis, pulmonary embolism, and infection.
CONCLUSIONS
These results suggest that liposuction can be a viable treatment alternative to compression therapy for lipedema in patients whose compression therapy has not been helpful. However, there is not enough evidence to say whether liposuction is as effective as compression for patients first presenting with lipedema.
PubMed: 38957726
DOI: 10.1097/GOX.0000000000005952 -
Ecology and Evolution Jul 2024Marine sponges play a vital role in the reef's benthic community; however, understanding how their diversity and abundance vary with depth is a major challenge,...
Marine sponges play a vital role in the reef's benthic community; however, understanding how their diversity and abundance vary with depth is a major challenge, especially on marginal reefs in areas deeper than 30 m. To help bridge this gap, we used underwater videos at 24 locations between 2- and 62-meter depths on a marginal reef system in the Southwestern Atlantic to investigate the effect of depth on the sponge metacommunity. Specifically, we quantified the abundance, density, and taxonomic composition of sponge communities, and decomposed their gamma () diversity into alpha () and beta () components. We also assessed whether beta diversity was driven by species replacement (turnover) or by nesting of local communities (nestedness). We identified 2020 marine sponge individuals, which belong to 36 species and 24 genera. As expected, deep areas (i.e., those greater than 30 m) presented greater sponge abundance and more than eightfold the number of sponges per square meter compared to shallow areas. About 50% of the species that occurred in shallow areas (<30 m) also occurred in deep areas. Contrarily to expectations, alpha diversity of rare ( ), typical ( ), or dominant ( ) species did not vary with depth, but the shallow areas had greater beta diversity than the deep ones, especially for typical ( ) and dominant ( ) species. Between 92.7% and 95.7% of the beta diversity was given by species turnover both inside and between shallow and deep areas. Our results support previous studies that found greater sponge abundance and density in deep areas and reveal that species sorting is stronger at smaller depths, generating more beta diversity across local communities in shallow than deep areas. Because turnover is the major driver at any depth, the entire depth gradient should be considered in management and conservation strategies.
PubMed: 38957700
DOI: 10.1002/ece3.11643 -
Parkinson's Disease 2024The aim of this study was to compare the Sniffin' Sticks 12-identification test (SIT-12), China-modified version of the SIT-12 test (Ch-SIT-12) and brief smell...
China's Modified Version of Sniffin' Sticks 12-Identification Test Used in Chinese Parkinson's Disease and Multiple System Patients: Comparison of Three Olfactory Testing Methods.
OBJECTIVES
The aim of this study was to compare the Sniffin' Sticks 12-identification test (SIT-12), China-modified version of the SIT-12 test (Ch-SIT-12) and brief smell identification test for Chinese (B-SITC) in Chinese population of Parkinson's disease (PD) and multiple system atrophy (MSA).
METHODS
36 patients with PD and 7 patients with MSA were enrolled in this study. Three olfactory testing methods (SIT-12, Ch-SIT-12, and B-SITC) were used to test the olfactory function in all participants. Furthermore, demographic and clinical data were collected.
RESULTS
There was no significant difference between three olfactory tests in patients with PD (B-SITC vs. SIT-12: =0.508; Ch-SIT-12 vs. B-SITC: =0.146; and SIT-12 vs. Ch-SIT-12: =0.375). Tremor-dominant (TD) subtypes have better olfactory function than akinetic-rigid dominant (ARD) subtypes when using Ch-SIT-12 (77.8% vs. 29.6%, =0.019) or B-SITC (55.6% vs. 14.8%, =0.026). There was a statistical difference between the PD and MSA using Ch-SIT-12 to test the olfactory function (=0.046).
CONCLUSIONS
Our results indicated that SIT-12, Ch-SIT-12 and B-SITC can be used for the detection of olfactory dysfunction in Chinese population of PD. TD subtypes may have better olfactory function than ARD subtypes. In addition, Ch-SIT-12 may be used to differentiate PD from MSA, but that should be confirmed in a larger population.
PubMed: 38957659
DOI: 10.1155/2024/3561881 -
Frontiers in Microbiology 2024Increased nitrogen deposition is a key feature of global climate change, however, its effects on the structure and assembling mechanisms of the nitrogen-fixing bacteria...
Increased nitrogen deposition is a key feature of global climate change, however, its effects on the structure and assembling mechanisms of the nitrogen-fixing bacteria present at the root surface remain to be elucidated. In this pursuit, we used NHNO to simulate nitrogen deposition in a 10-year-old plantation, and set up four deposition treatments, including control N0 (0 kg N hm a), low nitrogen N20 (20 kg N hm a), medium nitrogen N40 (40 kg N hm a) and high nitrogen N160 (160 kg N hm a). The results showed that nitrogen deposition affected the soil nitrogen content and the structure of the nitrogen-fixing bacterial community. Low nitrogen deposition was conducive for nitrogen fixation in mature plantation. With increasing nitrogen deposition, the dominant soil nitrogen-fixing bacterial community shifted from Desulfobulbaceae to Bradyrhizobium. When nitrogen deposition was below 160 kg N hm a, the soil organic matter content, total nitrogen content, nitrate nitrogen content, ammonium nitrogen content, urease activity, soil pH and nitrate reductase activity influenced the composition of the nitrogen-fixing bacterial community, but the stochastic process remained the dominant factor. The results indicate that the strains of and sp. ORS 285 can be used as indicator species for excessive nitrogen deposition.
PubMed: 38957615
DOI: 10.3389/fmicb.2024.1414724 -
RSC Advances Jun 2024In this research work, we have examined the influence of silver halide doping on the dielectric dispersion and AC conduction of elemental selenium. The in-depth...
In this research work, we have examined the influence of silver halide doping on the dielectric dispersion and AC conduction of elemental selenium. The in-depth investigation shows that when the dopant silver halides are incorporated, there are noticeable changes in the parent selenium's dielectric constant ('), dielectric loss (''), and AC conductivity ( ). When we frame the discussion of the obtained results with the relevant transport models, we found that in pure selenium and Se(AgI), conduction is primarily due to polaron hopping and follows the correlated barrier hopping (CBH) model. In contrast, Se(AgBr) predominantly exhibits non-overlapping small polaron tunneling (NSPT). Interestingly, Se(AgCl) demonstrates both NSPT and CBH conduction mechanisms, depending on the temperature range: NSPT is dominant between 303 K and 313 K, while CBH prevails from 318 K to 338 K. Additionally, our findings revealed the presence of both the Meyer-Neldel rule (MNR) and its reverse in the prepared silver halide chalcogenide alloys. The best optimization of dielectric constant and loss is observed for silver iodide as compared to silver chloride and silver bromide. Comparison with other silver-containing chalcogenide glasses indicates the better dielectric performance of the present silver halides containing selenium.
PubMed: 38957577
DOI: 10.1039/d4ra02999b -
Atmospheric Environment (Oxford,... Oct 2014A series of wildfires in northern Quebec, early July 2002, and in southern Quebec, late May 2010, resulted in severe air pollution downwind. Downwind exposures were...
A series of wildfires in northern Quebec, early July 2002, and in southern Quebec, late May 2010, resulted in severe air pollution downwind. Downwind exposures were investigated to estimate the impact on outdoor and indoor environments. The plumes derived from the wildfires resulted in an increase of over 10 ppbv ozone (O) concentrations in both major cities and rural areas, while O enhancement was not observed at locations adjacent to wildfire burning areas. Temporal trend in PM concentration showed a peak of 105.5 μg/m on July 7, 2002, while on May 31, 2010 the peak was 151.1 μg/m in Boston downwind. PM speciation showed similar trends between the episodes, along with spikes in the PM/PM ratio, and in the concentrations of Black Carbon, ΔC (i.e., UV absorbing compounds minus Black Carbon), Organic Carbon (OC), potassium, and chlorine. OC was the most dominant constituent of the PM mass in the wildfires. The dominant specific carbon fractions include OC fraction 3, pyrolysis carbon, and EC fraction 1, likely due to pyrolysis of structural components of wood. Indoor PM peaks at two houses corresponded well with the ambient PM peak, along with the elemental composition, which could indicate an impact of wildfires on indoor air pollution exposure.
PubMed: 38957569
DOI: 10.1016/j.atmosenv.2014.07.008