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Objective·To verify the performance and explore the clinical application value of a multi-modal pulmonary nodule diagnosis model combined with metabolic fingerprints, protein biomarker CEA and Image-AI via random forest (MPI-RF).Methods·This study enrolled 289 patients with pulmonary nodules who were admitted to the Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine and were detected by low-dose helical computed tomography (LDCT). The patients were divided into malignant nodule group (n=197) and benign nodule group (n=92) based on postoperative pathological results, and the basic information of the two groups was collected and compared. Electrochemiluminescence was used to detect the preoperative serum CEA levels of the patients in the two groups, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used to detect the serum metabolic fingerprints, and the CT image artificial intelligence model Image-AI was used to calculate the image scores. CEA data, serum metabolic fingerprints data and image scores were integrated and input into MPI-RF to calculate the malignant probability score of each patient. The receiver operator characteristic curve (ROC curve) and area under the curve (AUC) were used to evaluate the performance of different models, and the DeLong test was used for comparative analysis, including the diagnostic performance of MPI-RF in different types (solid nodule, pure ground-glass nodule and part-solid nodule) and sizes (diameter

Area-selective atomic layer deposition (ALD) of dielectrics on chemically similar growth and nongrowth surfaces is very challenging. In this study, we use aminosilane inhibitors to achieve selective blocking of ALD of Al2O3 on plasma-deposited SiO2 versus plasma-deposited SiNx. The SiO2 and SiNx surfaces were exposed to bis(dimethylamino)dimethylsilane followed by (N,N-dimethylamino)trimethylsilane through the vapor phase at 150 °C. At the same substrate temperature, Al2O3 films were grown by ALD using dimethylaluminum isoproxide and H2O. In situ surface infrared spectroscopy shows that aminosilane inhibitors react with almost all the surface −SiOH groups on SiO2, but reaction with surface −NHx groups on the SiNx surface is incomplete, thereby leaving potential growth sites for ALD of Al2O3. In situ ellipsometry results shows that a ∼2.7 nm Al2O3 film can be selectively deposited on SiNx versus SiO2. Upon exposure of the plasma-deposited SiNx to the atmosphere, a higher attachment of aminosilanes and longer nucleation delay during the ALD of Al2O3 were observed, indicating the need to remove the native surface oxynitride prior to functionalization. This study shows that while fully passivating the nongrowth surface is necessary for achieving growth inhibition, ALD can initiate on a partially passivated growth surface. [ABSTRACT FROM AUTHOR]

During area-selective atomic layer deposition (ALD) based on growth inhibitors, nucleation eventually occurs as the metal precursor reacts with the surface through secondary pathways. We show that ALD of Al2O3 on functionalized SiO2 can be significantly delayed by using a lower reactivity, heteroleptic precursor at well below the saturation dose. [ABSTRACT FROM AUTHOR]

During area-selective atomic layer deposition (ALD) based on growth inhibitors, nucleation eventually occurs as the metal precursor reacts with the surface through secondary pathways. We show that ALD of Al2O3 on functionalized SiO2 can be significantly delayed by using a lower reactivity, heteroleptic precursor at well below the saturation dose. [ABSTRACT FROM AUTHOR]

The authors have investigated the surface reaction mechanisms during the atomic layer deposition (ALD) of ZrO2 from tetrakis(ethylmethylamino)zirconium (TEMAZ) with H2O, C2H5OH, and H2O-C2H5OH mixture as the oxygen sources. The ligand-exchange reactions were characterized using in situ attenuated total reflection Fourier transform infrared spectroscopy, and the film growth was recorded using in situ four-wavelength ellipsometry. In the H2O-based ALD process, as expected, surface –OH groups were the reactive sites for TEMAZ, and a growth per cycle (GPC) of ∼1.1 Å was obtained at 200 °C. Contrary to previous reports, no film growth was observed for the C2H5OH-based ALD process. During the TEMAZ half-cycle, the –OC2H5-terminated surface obtained after the C2H5OH half-cycle simply underwent ligand exchange without any addition of Zr to the surface, most likely forming Zr[N(CH3)(C2H5)]4 – x[OC2H5]x (1 ≤ x ≤ 3) as the byproduct. Film growth was observed during the ALD of ZrO2 using an H2O-C2H5OH mixture as the oxygen source. The addition of C2H5OH reduced the surface hydroxyl coverage by forming surface ethoxide sites, which did not contribute to film growth. This in turn led to a lower GPC, ∼0.6 Å, compared to the TEMAZ/H2O ALD process. [ABSTRACT FROM AUTHOR]

While whole-genome sequencing has been applied extensively to investigate the genetic diversity of global populations, ethnic minority groups in Pakistan are generally underrepresented. In particular, little is known about the genetic origin and highland adaptation of the Pamirian Wakhi people. According to Chinese historical records, the geographical location and language usage of Wakhi may be closely related to Xinjiang Tajiks (XJT). In this study, based on high-coverage (∼30×) whole-genome sequencing of eight Wakhi and 25 XJT individuals, we performed data analyses together with worldwide populations to gain insights into their genetic composition, demography, and adaptive evolution to the highland environment. The Wakhi derived more than 85% of their ancestry from West Eurasian populations (European ∼44.5%, South Asian ∼42.2%) and 10% from East Eurasian populations (Siberian ∼6.0%, East Asian ∼4.3%). Modeling the admixture history of the Wakhi indicated that the early West-East admixture occurred approximately 3,875-2,250 years ago and that the recent admixture occurred 750-375 years ago. We identified selection signatures across EGLN3, in particular, a distinctive evolutionary signature was observed, and a certain underlying selected haplotype showed higher frequency (87.5%) in the Wakhi than in nearby XJT and other highlanders. Interestingly, we found high-frequency archaic sequences in the Wakhi genome, which overlapped with several genes related to cellular signaling transduction, including MAGI2, previously associated with high-altitude adaptation. Our analysis indicates that the Wakhi are distinct from the XJTs and Tajikistan Tajiks, and shed light on the Wakhi's ancestral origin and genetic basis of high-altitude adaptation., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

During area-selective atomic layer deposition (ALD) based on growth inhibitors, nucleation eventually occurs as the metal precursor reacts with the surface through secondary pathways. We show that ALD of Al 2 O 3 on functionalized SiO 2 can be significantly delayed by using a lower reactivity, heteroleptic precursor at well below the saturation dose.

Small-molecule inhibitors are promising for achieving area-selective atomic layer deposition (ALD) due to their excellent compatibility with industrial processes. In this work, we report on growth inhibition during ALD of Al 2 O 3 on a SiO 2 surface functionalized with small-molecule aminosilane inhibitors. The SiO 2 surface was prefunctionalized with bis(dimethylamino)dimethylsilane (BDMADMS) and ( N , N -dimethylamino)trimethylsilane (DMATMS) through solution and the vapor phase. ALD of Al 2 O 3 using dimethylaluminum isopropoxide (DMAI) and H 2 O was performed on these functionalized SiO 2 surfaces. Our in situ four-wavelength ellipsometry measurements show superior growth inhibition when using BDMADMS and DMATMS in sequence over just using BDMADMS or DMATMS. Vapor phase functionalization provided a growth delay of ∼30 ALD cycles, which was similar to solution-based functionalization. Using in situ attenuated total reflection Fourier transform infrared spectroscopy, we show that the interaction of DMAI with SiO 2 surfaces leads to pronounced changes in absorbance for the Si-O-Si phonon mode without any detectable DMAI absorbed on the SiO 2 surface. Detailed analysis of the infrared spectra revealed that the decrease in absorbance was likely caused by the coordination of Al in DMAI to O atoms in surface Si-O-Si bonds without the breaking the Si-O-Si bonds. Finally, we postulate that a minimal amount of DMAI remains adsorbed on surface Si-O-Si bonds even after purging, which can initiate ALD of Al 2 O 3 on functionalized SiO 2 : this highlights the need for higher surface coverage for enhanced steric blocking.

Selective functionalization of dielectric surfaces is required for area-selective atomic layer deposition and etching. We have identified precursors for the selective gas-phase functionalization of plasma-deposited SiO 2 and SiN x surfaces with hydrocarbons. The corresponding reaction mechanism of the precursor molecules with the two surfaces was studied using in situ surface infrared spectroscopy. We show that at a substrate temperature of 70 °C, cyclic azasilanes preferentially react with an -OH-terminated SiO 2 surface over a -NH x -terminated SiN x surface with an attachment selectivity of ∼5.4, which is limited by the partial oxidation of the SiN x surface. The cyclic azasilane undergoes a ring-opening reaction where the Si-N bond cleaves upon the reaction with surface -OH groups forming a Si-O-Si linkage. After ring opening, the backbone of the grafted hydrocarbon is terminated with a secondary amine, -NHCH 3 , which can react with water to form an -OH-terminated surface and release CH 3 NH 2 as the product. The surface coverage of the grafted cyclic azasilane is calculated as ∼3.3 × 10 14 cm -2 , assuming that each reacted -OH group contributes to one hydrocarbon linkage. For selective attachment to SiN x over SiO 2 surfaces, we determined the reaction selectivity of aldehydes. We demonstrate that aldehydes selectively attach to SiN x over SiO 2 surfaces, and for the specific branched aliphatic aldehyde used in this work, almost no reaction was detected with the SiO 2 surface. A fraction of the aldehyde molecules reacts with surface -NH 2 groups to form an imine (Si-N═C) surface linker with H 2 O released as the byproduct. The other fraction of the aldehydes also reacts with surface -NH 2 groups but do not undergo the water-elimination step and remains attached to the surface as an aminoalcohol (Si-NH-COH-). The surface coverage of the grafted aldehyde is calculated as ∼9.8 × 10 14 cm -2 using a known infrared absorbance cross-section for the -C(CH 3 ) 3 groups.