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1.
Reg Anesth Pain Med ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991713

ABSTRACT

BACKGROUND: This cadaveric study aimed to analyze injectate spread to target nerves during a single-injection, ultrasound-guided intertransverse process block. METHODS: An ultrasound-guided intertransverse process block with three different injectate volumes was administered to 12 cadavers. Each hemithorax was subjected to computer-generated random allocation of 10, 15, or 20 mL ultrasound-guided, single-injection intertransverse process block at the T2 vertebral level. Latex dye solution was injected into each hemithorax in accordance with the allocated volume. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at various injection levels was examined via dissection. RESULTS: Injectate spread into the dorsal rami was observed in seven of eight (87.5%), seven of eight (87.5%), and all eight (100%) of the 10, 15, and 20 mL specimens, respectively. In all 20 mL specimens, consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion was observed. CONCLUSIONS: An injectate volume of 20 mL was required for consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion in an intertransverse process block. Although an augmented injectate volume was associated with an increased likelihood of target nerve staining, consistent staining of the sympathetic ganglion, rami communicans, and ventral ramus was not observed, even at a volume of 20 mL. The current study presents initial findings suggesting that as opposed to a sympathetic ganglion block, a 20 mL intertransverse process block may act as a feasible substitute for dorsal root ganglion, spinal nerve, and medial branch blocks within a clinical context.

2.
Biomed Eng Lett ; 14(4): 867-876, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38946817

ABSTRACT

Purpose: The sacroiliac joint (SIJ), a synovial joint with irregular surfaces, is crucial for stabilizing the body and facilitating daily activities. However, recent studies have reported that 15-30% of lower back pain can be attributed to instability in the SIJ, a condition collectively referred to as sacroiliac joint dysfunction (SIJD). The aim of this study is to investigate how the morphological characteristics of the auricular surface may influence the SIJ range of motion (ROM) and to examine differences in SIJ ROM between females and males, thereby contributing to the enhancement of SIJD diagnosis and treatment. Methods: We measured SIJ ROM using motion-analysis cameras in 24 fresh cadavers of Korean adults (13 males and 11 females). Using three-dimensional renderings of the measured auricular surface, we investigated the correlations between the morphological characteristics of the auricular surface and the ROM of the SIJ. Results: The SIJ ROM was between 0.2° and 6.7° and was significantly greater in females (3.58° ± 1.49) compared with males (1.38° ± 1.00). Dividing the participants into high-motion (3.87° ± 1.19) and low-motion (1.13° ± 0.62) groups based on the mean ROM (2.39°) showed no significant differences in any measurements. Additionally, bone defects around the SIJ were identified using computed tomography of the high-motion group. In the low-motion group, calcification between auricular surfaces and bone bridges was observed. Conclusion: This suggests that the SIJ ROM is influenced more by the anatomical structures around the SIJ than by the morphological characteristics of the auricular surface.

3.
Medicina (Kaunas) ; 60(5)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38792872

ABSTRACT

Background and Objectives: The interspace between the popliteal artery and the posterior capsule of the knee (iPACK) block has been widely used in perioperative settings to control posterior knee pain and can additionally be used for chronic knee pain. In this cadaveric study, we aimed to investigate the needle tip position and its proximity to the articular branch of the tibial nerve (ABTN) during an iPACK-targeted radiofrequency procedure. Materials and Methods: An ultrasound-guided iPACK block was performed on 20 knees of 10 cadavers. We injected 0.1 mL each of blue and green gelatinous dye near the tibial artery (point A) and posterior knee capsule (point B), respectively, and evaluated the spread of both around the ABTN. For a hypothetical conventional radiofrequency ablation (RFA) lesion (diameter, 2.95 mm) and cooled RFA lesion (diameter, 4.9 mm), we counted the number of specimens in which the ABTNs would be captured. Results: The percentage of specimens in which the ABTN would be captured by a cooled RFA lesion was 64.71% at point A and 43.75% at point B (p = 0.334). Meanwhile, the percentage of specimens in which the ABTN would be captured by a conventional RFA lesion was 58.82% from point A and 25% from point B (p = 0.065). Conclusions: When performing an RFA-based iPACK block, the needle tip may be positioned either lateral to the tibial artery or in the space between the posterior knee capsule and the tibial artery. However, more studies with larger samples are needed to verify these results before the clinical use of this procedure can be recommended.


Subject(s)
Cadaver , Popliteal Artery , Radiofrequency Ablation , Humans , Popliteal Artery/surgery , Radiofrequency Ablation/methods , Female , Male , Nerve Block/methods , Needles , Aged , Knee Joint/surgery , Aged, 80 and over , Tibial Nerve , Ultrasonography, Interventional/methods
4.
J Exerc Rehabil ; 20(1): 34-41, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38433853

ABSTRACT

The purpose of this study is to analyze the effect of proprioceptive exercise training on soccer skills and physical fitness in young soccer players. Nineteen young soccer players participated in the study. Participants were divided into proprioceptive exercises training (PT) and control (Cont) groups. The physical fitness and soccer skill performance test assessed at pre- and posttraining. Balance ability and power significantly improved in both groups after 8 weeks of training (P<0.05). Dribble in the PT group was similar between pre- and posttraining, with a statistically significant difference in the Cont group (P<0.05). There were no significant differences within and between groups according to training in the left and right feet for juggling. The PT and Cont groups did not differ significantly regarding short passes posttraining. However, a significant improvement in long passes was observed in the PT group after training period (P<0.05). Shooting was no different between and within the groups. In conclusion, these inconsistent findings are thought to be due to the applied exercise method, training duration, and the specificity of the physical growth period of the young players. Therefore, it is necessary to increase the frequency and time of proprioceptive exercise training and apply factors for cognitive ability improvement to training programs for young soccer players in future studies. These studies could suggest appropriate training methods necessary to improve the performance of young soccer players.

6.
Leg Med (Tokyo) ; 66: 102363, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38065055

ABSTRACT

The nose is a prominent feature for facial recognition and reconstruction. To investigate the relationship of the nasal shape with the piriform aperture in Korean adults and juveniles, we performed regression analysis. By regression analysis, prediction equations for nasal shape were obtained in relation to the shape of the piriform aperture considering sex and age groups. Three-dimensional skull and face models, rendered from computed tomography images, were assessed (331 males and 334 females). Juveniles (<20 years) were divided into three age groups according to the development of the dentition. Adults were divided into three age groups of two decades each, according to their age. To measure the nasal area, nine landmarks and nine measurements were chosen, while seven landmarks and five measurements were selected to measure the piriform aperture area. Four measurements were defined to explain the direct relationship between the nasal aperture and nasal shape. First, descriptive statistical analyses were performed according to sex and age groups. Subsequently, the correlation of nasal soft tissue measurements with piriform measurements was analyzed. Last, we performed a linear regression analysis of the measurements with higher correlations, considering sex and age groups as variables. Prediction equations were used to estimate the nasal bridge length, height, protrusion, and width. Equations considering sex and age groups showed better explanation ability. Measurements related to the height of the nasal bridge presented improvement. This study may assist in the more accurate approximation of nasal shape in facial reconstruction.


Subject(s)
Forensic Anthropology , Imaging, Three-Dimensional , Adult , Male , Female , Humans , Forensic Anthropology/methods , Nose/diagnostic imaging , Nose/anatomy & histology , Regression Analysis , Skull/anatomy & histology
7.
Anat Sci Educ ; 17(2): 396-412, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38053470

ABSTRACT

Anatomy instructional methods varied widely during the COVID-19 pandemic and programs are assessing innovations for retention. Learning preferences were assessed among medical students dichotomized as elective dissectors (ED) or non-dissectors (ND) during the COVID-19 partial re-opening in 2020 (preclinical) and again in 2022 after clinical exposure (post-clinical) to assess the viability of elective dissection post-pandemic. A mixed-method approach was used for the assessment of test scores, learning preference surveys, learning activities rankings, and thematic analyses. No significant differences occurred in anatomy examination scores. Dissection was considered useful by both preclinical groups but significantly more so by ED, while the presence of an instructor was significantly preferred by ED although a majority of ND agreed. Elective dissection was significantly preferred by ND but also by a large minority of ED students. Pre- and post-clinical ND believed that elective dissection offered more academic flexibility, did not hinder clinical learning, and did not negatively impact medical education. The corresponding ED stated that confidence improved, clinical experiences were enhanced, and dissection was irreplaceable. Preclinical ND preferred self-learning, while ED students preferred online learning, but these differences largely disappeared post-clinically. Learning activity rankings were not significantly different among all groups (ND, ED, preclinical, and post-clinical). A hybrid laboratory with a virtual learning environment ranked highest across groups and preferences increased over time suggesting that students benefited from this instructional method during clinical exposure. The absence of laboratory experience ranked lowest, and preference decreased over time suggesting that anatomy dissection is valued.


Subject(s)
Anatomy , COVID-19 , Education, Medical, Undergraduate , Students, Medical , Humans , Pandemics , Anatomy/education , Learning , Education, Medical, Undergraduate/methods
8.
ACS Appl Mater Interfaces ; 16(1): 1342-1350, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38116929

ABSTRACT

In this study, three nitrogen-containing aluminum-based metal-organic frameworks (Al-MOFs), namely, CAU-10pydc, MOF-303, and KMF-1, were investigated for the efficient separation of a C2H2/CO2 gas mixture. Among these three Al-MOFs, KMF-1 demonstrated the highest selectivity for C2H2/CO2 separation (6.31), primarily owing to its superior C2H2 uptake (7.90 mmol g-1) and lower CO2 uptake (2.82 mmol g-1) compared to that of the other two Al-MOFs. Dynamic breakthrough experiments, using an equimolar binary C2H2/CO2 gas mixture, demonstrated that KMF-1 achieved the highest separation performance. It yielded 3.42 mmol g-1 of high-purity C2H2 (>99.95%) through a straightforward desorption process under He purging at 298 K and 1 bar. To gain insights into the distinctive characteristics of the pore surfaces of structurally similar CAU-10pydc and KMF-1, we conducted computational simulations using canonical Monte Carlo and dispersion-corrected density functional theory methods. These simulations revealed that the secondary amine (C2N-H) groups in KMF-1 played a more significant role in differentiating between C2H2 and CO2 compared to that of the N atoms in CAU-10pydc and MOF-303. Consequently, KMF-1 emerged as a promising adsorbent for the separation of high-purity C2H2 from binary C2H2/CO2 gas mixtures.

9.
Reg Anesth Pain Med ; 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37657889

ABSTRACT

BACKGROUND: We compared the spread of an injectate into the thoracic sympathetic chain resulting from a single-injection intertransverse process (ITP) block with that of a single-injection PV block at the T2 level. METHODS: Sixteen soft-embalmed cadavers were used. The right hemithorax was randomly allocated to receive either an ultrasound-guided single-injection ITP block or ultrasound-guided single-injection PV block at the T2 vertebral level, with the opposite block administered to the other side. Approximately 10 mL of latex dye solution was injected into each hemithorax using a random allocation technique. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at the injection and additional levels was examined by dissection. RESULTS: The injectate spread into the T2 sympathetic ganglion on both ITP (11/16, 68.8%) and PV (16/16, 100%) blocks. The ITP block demonstrated greater uniformity of dye staining in both the dorsal rami and dorsal root ganglion, which contrasts with the less consistent staining outcomes of the PV block in these regions. CONCLUSIONS: At the T2 level, we observed a lower efficacy of the ITP block for analgesic coverage of the sympathetic nerve. This suggested a potential preference by clinicians for the application of the T2 PV block over the ITP block, specifically for the management of sympathetically maintained pain in the upper extremities. In addition, our findings may hint at the potential advantages of the ITP block in specific clinical contexts where targeted nerve involvement, such as the medial branch block or dorsal root ganglion block, is sought.

10.
Korean J Pain ; 36(3): 328-334, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37345308

ABSTRACT

Background: Among the four genicular nerves innervating the anterior aspect of the knee, the inferior lateral genicular nerve has been omitted as a target of blocking. Some authors have suggested that the inferior lateral genicular nerve of the knee might pass beneath the lateral collateral ligament of knee. The authors aimed to study the location of the inferior lateral genicular nerve and the spread of injectate during the inferior lateral genicular nerve block. Methods: In ten knees from fresh frozen cadavers, the authors performed on each an ultrasound-guided block of the inferior lateral genicular nerve of the knee just below the lateral collateral ligament. The needle was inserted below the lateral collateral ligament, and 2 mL of blue dye was injected. A week later, the cadavers were dissected, and the existence of the inferior lateral genicular nerve and the spread of dye around it was investigated. Results: The proportion of inferior lateral genicular nerves branching from the common peroneal nerve was found in 8 of 10 (80.0%) cadavers. Of these eight cadavers with inferior lateral genicular nerve, five specimens (62.5%) were stained with blue dye. The common peroneal nerve was not infiltrated with dye in any specimens. Conclusions: When 2 mL of dye was inserted inferiorly to the lateral collateral ligament, the inferior lateral genicular nerve could be blocked in 62.5% of specimens. Because the common peroneal nerve was not involved in any specimen, motor weakness would be avoided with this method.

11.
ACS Appl Mater Interfaces ; 15(25): 30975-30984, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37310803

ABSTRACT

A series of Al-based isomorphs (CAU-10H, MIL-160, KMF-1, and CAU-10pydc) were synthesized using isophthalic acid (ipa), 2,5-furandicarboxylic acid (fdc), 2,5-pyrrole dicarboxylic acid (pyrdc), and 3,5-pyridinedicarboxylic acid (pydc), respectively. These isomorphs were systematically investigated to identify the best adsorbent for effectively separating C2H6/C2H4. All CAU-10 isomorphs exhibited preferential adsorption of C2H6 over that of C2H4 in mixture. CAU-10pydc exhibited the best C2H6/C2H4 selectivity (1.68) and the highest C2H6 uptake (3.97 mmol g-1) at 298 K and 1 bar. In the breakthrough experiment using CAU-10pydc, 1/1 (v/v) and 1/15 (v/v) C2H6/C2H4 gas mixtures were successfully separated into high-purity C2H4 (>99.95%), with remarkable productivities of 14.0 LSTP kg-1 and 32.0 LSTP kg-1, respectively, at 298 K. Molecular simulations revealed that the exceptional separation performance of CAU-10pydc originated from the increased porosity and reduced electron density of the pyridine ring of pydc, leading to a relatively larger decrease in π-π interactions with C2H4 than in the C-H···π interactions with C2H6. This study demonstrates that the pore size and geometry of the CAU-10 platform are modulated by the inclusion of heteroatom-containing benzene dicarboxylate or heterocyclic rings of dicarboxylate-based organic linkers, thereby fine-tuning the C2H6/C2H4 separation ability. CAU-10pydc was determined to be an optimum adsorbent for this challenging separation.

12.
Adv Sci (Weinh) ; 10(21): e2301311, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37178363

ABSTRACT

Water adsorption-driven heat transfer (AHT) technology has emerged as a promising solution to address crisis of the global energy consumption and environmental pollution of current heating and cooling processes. Hydrophilicity of water adsorbents plays a decisive role in these applications. This work reports an easy, green, and inexpensive approach to tuning the hydrophilicity of metal-organic frameworks (MOFs) by incorporating mixed linkers, isophthalic acid (IPA), and 3,5-pyridinedicarboxylic acid (PYDC), with various ratios in a series of Al-xIPA-(100-x)PYDC (x: feeding ratio of IPA) MOFs. The designed mixed-linkers MOFs show a variation of hydrophilicity along the fraction of the linkers. Representative compounds with a proportional mixed linker ratio denoted as KMF-2, exhibit an S-shaped isotherm, an excellent coefficient of performance of 0.75 (cooling) and 1.66 (heating) achieved with low driving temperature below 70 °C which offers capability to employ solar or industrial waste heat, remarkable volumetric specific energy capacity (235 kWh m-3 ) and heat-storage capacity (330 kWh m-3 ). The superiority of KMF-2 to IPA or PYDC-containing single-linker MOFs (CAU-10-H and CAU-10pydc, respectively) and most of benchmark adsorbents illustrate the effectiveness of the mixed-linker strategy to design AHT adsorbents with promising performance.

13.
Sci Rep ; 13(1): 4014, 2023 03 10.
Article in English | MEDLINE | ID: mdl-36899072

ABSTRACT

Eyebrows are the most important facial feature in facial recognition with its shape rated to be more helpful than color or density for facial reconstruction or approximation. However, little extant research has estimated the position and morphological territory of the eyebrow from the orbit. Three-dimensional craniofacial models, produced from CT scans of 180 Koreans autopsied at the National Forensic Service Seoul Institute, were used to conduct metric analyses of subjects (125 males and 55 females) between 19 and 49 (mean 35.1) years. We employed 18 craniofacial landmarks to examine the morphometry of the eyebrow and orbit with 35 pairs of distances per subject measured between landmark and reference planes. Additionally, we used linear regression analyses to predict eyebrow shape from the orbit for every possible combination of variables. The morphology of the orbit has more influence on the position of the superior margin of the eyebrow. In addition, the middle part of the eyebrow was more predictable. The highest point of the eyebrow in female was located more medially than the male. Based on our findings, the equations for estimating the position of the eyebrow from the shape of the orbit is useful information for face reconstruction or approximation.


Subject(s)
Eyebrows , Orbit , Humans , Male , Female , Eyebrows/anatomy & histology , Tomography, X-Ray Computed , Regression Analysis , Forensic Medicine , Imaging, Three-Dimensional
14.
Anesth Analg ; 136(3): 597-604, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36727847

ABSTRACT

BACKGROUND: The pericapsular nerve group (PENG) block was recently suggested as a regional technique for managing acute pain after hip surgery. However, few anatomical studies have confirmed the spread of injectate during the PENG block. This cadaver study aimed to analyze injectate spread to the target nerves during single-injection ultrasound-guided PENG block. METHODS: Ultrasound-guided PENG block with 3 different injectate volumes (10, 20, or 30 mL) was performed in 18 cadavers. Injectate spread by the volume was first evaluated on computed tomography, followed by cadaver dissection. The spread of the dye over the pelvis and lower limb was evaluated. RESULTS: The articular branches of the femoral nerve were stained nearly sufficiently with 20- and 30-mL specimens. The femoral nerve itself was stained simultaneously in six of 12 (50%) 20-mL specimens and 12 of 12 (100%) 30-mL specimens. The accessory obturator nerve was observed only in three (9%) of 36 specimens. The articular branches of the obturator nerve were rarely affected, regardless of injectate volume (1/12, 10 mL specimens; 2/12, 20 mL specimens; 1/12, 30 mL specimens; P > .999). Rather, the obturator nerve was affected. However, the obturator nerve was not stained consistently even with 30 mL of injectate (50%). CONCLUSIONS: After combining the dissection and radiological findings, the single-injection ultrasound-guided PENG blocks with volumes of 10, 20, and 30 mL do not support motor sparing or selective anterior hip capsule innervation in a clinical setting. If early rehabilitation is needed, high-volume PENG block might not be the ideal option, and persisting pain after PENG block might be attributed in part to the lack of obturator nerve articular branches blockade.


Subject(s)
Femoral Nerve , Nerve Block , Humans , Ultrasonography, Interventional/methods , Nerve Block/adverse effects , Nerve Block/methods , Obturator Nerve/diagnostic imaging , Cadaver
15.
Anat Histol Embryol ; 52(1): 101-114, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36317584

ABSTRACT

Educational technologies in veterinary medicine aim to train veterinarians faster and improve clinical outcomes. COVID-19 pandemic, shifted face-to-face teaching to online, thus, the need to provide effective education remotely was exacerbated. Among recent technology advances for veterinary medical education, extended reality (XR) is a promising teaching tool. This study aimed to develop a case resolution approach for radiographic anatomy studies using XR technology and assess students' achievement of differential diagnostic skills. Learning objectives based on Bloom's taxonomy keywords were used to develop four clinical cases (3 dogs/1 cat) of spinal injuries utilizing CT scans and XR models and presented to 22 third-year veterinary medicine students. Quantitative assessment (ASMT) of 7 questions probing 'memorization', 'understanding and application', 'analysis' and 'evaluation' was given before and after contact with XR technology as well as qualitative feedback via a survey. Mean ASMT scores increased during case resolution (pre 51.6% (±37%)/post 60.1% (± 34%); p < 0.01), but without significant difference between cases (Kruskal-Wallis H = 2.18, NS). Learning objectives were examined for six questions (Q1-Q6) across cases (C1-4): Memorization improved sequentially (Q1, 2 8/8), while Understanding and Application (Q3,4) showed the greatest improvement (26.7%-76.9%). Evaluation and Analysis (Q5,6) was somewhat mixed, improving (5/8), no change (3/8) and declining (1/8).Positive student perceptions suggest that case studies' online delivery was well received stimulating learning in diagnostic imaging and anatomy while developing visual-spatial skills that aid understanding cross-sectional images. Therefore, XR technology could be a useful approach to complement radiological instruction in veterinary medicine.


Subject(s)
Cat Diseases , Dog Diseases , Education, Distance , Education, Veterinary , Students, Medical , Animals , Dogs , Humans , COVID-19/epidemiology , Dog Diseases/diagnostic imaging , Learning , Pandemics , Tomography, X-Ray Computed/veterinary , Cat Diseases/diagnostic imaging , Education, Veterinary/organization & administration , Students, Medical/psychology , Education, Distance/organization & administration , Educational Measurement
16.
QJM ; 116(3): 197-204, 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-36200913

ABSTRACT

BACKGROUND: Apelin is an endogenous neuropeptide that binds to the G-protein-coupled receptor (APJ) and participates in a variety of physiological processes in the heart, lungs and other peripheral organs. Intriguingly, [Pyr1]-Apelin-13, a highly potent pyroglutamic form of apelin, has the potential to bind to and be degraded by angiotensin-converting enzyme 2 (ACE2). ACE2 is known to operate as a viral receptor in the early stages of severe acute respiratory coronavirus (SARS-CoV-2) infection. AIM: This study aimed to determine if apelin protects against SARS-CoV-2 infection by inhibiting ACE2 binding to SARS-CoV-2 spike protein. DESIGN AND METHODS: To determine whether [Pyr1]-Apelin-13 inhibits ACE2 binding to the SARS-CoV-2 spike protein (S protein), we performed a cell-to-cell fusion assay using ACE2-expressing cells and S protein-expressing cells and a pseudovirus-based inhibition assay. We then analyzed publicly available transcriptome data while focusing on the beneficial effects of apelin on the lungs. RESULTS: We found that [Pyr1]-Apelin-13 inhibits cell-to-cell fusion mediated by ACE2 binding to the S protein. In this experiment, [Pyr1]-Apelin-13 protected human bronchial epithelial cells, infected with pseudo-typed lentivirus-producing S protein, against viral infection. In the presence of [Pyr1]-Apelin-13, the level of viral spike protein expression was also reduced in a concentration-dependent manner. Transcriptome analysis revealed that apelin may control inflammatory responses to viral infection by inhibiting the nuclear factor kappa B pathway. CONCLUSION: Apelin is a potential therapeutic candidate against SARS-CoV-2 infection.


Subject(s)
COVID-19 , Humans , Angiotensin-Converting Enzyme 2/pharmacology , SARS-CoV-2/metabolism , Apelin/pharmacology , COVID-19 Drug Treatment , Peptidyl-Dipeptidase A/metabolism
17.
ACS Appl Mater Interfaces ; 14(51): 56707-56714, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36516324

ABSTRACT

Among the most promising methods by which to capture CO2 from flue gas, the emission of which has accelerated global warming, is energy-efficient physisorption using metal-organic framework (MOF) adsorbents. Here, we present a novel cuprous-based ultramicroporous MOF, Cu(adci)-2 (adci- = 2-amino-4,5-dicyanoimidazolate), which was rationally synthesized by combining two strategies to design MOF physisorbents for enhanced CO2 capturing, i.e., aromatic amine functionalization and the introduction of ultramicroporosity (pore size <7 Å). Synchrotron powder X-ray diffraction and a Rietveld analysis reveal that the Cu(adci)-2 structure has one-dimensional square-shaped channels, in each of which all affiliated ligands, specifically NH2 groups at the 2-position of the imidazolate ring, have the same orientation, with a pair of NH2 groups therefore facing each other on opposite sides of the channel walls. While Cu(adci)-2 exhibits a high CO2 adsorption capacity (2.01 mmol g-1 at 298 K and 15 kPa) but a low zero-coverage isosteric heat of adsorption (27.5 kJ mol-1), breakthrough experiments under dry and 60% relative humidity conditions show that its CO2 capture ability is retained even in the presence of high amounts of moisture. In a Monte Carlo simulation and a radial distribution analysis, the preferential CO2 binding site of Cu(adci)-2 was predicted to be between two ligands, forming a sandwich-like structure and implying that its CO2 adsorption properties originate from the enhancement of Lewis base-acid and London dispersion interactions due to the amino groups and ultramicroporosity, respectively.

18.
Transl Res Anat ; 272022 Jun.
Article in English | MEDLINE | ID: mdl-36133355

ABSTRACT

Background: The purpose of this study is to characterize a full-term conjoined twins' cadaver curated by Dr. Jacob Henle sometime between 1844 and 1852 and demonstrate digital distribution of an old and rare medical museum specimen using an extended reality (XR) model workflow. Methods: The cadaver (Preparation 296) is in the Department of Anatomy and Cell Biology at the University of Heidelberg. An XR display workflow comprises image capture, segmentation, and visualization using CT/MR scans derived from the cadaver. Online radiology presentation to medical students focuses on diagnostic characteristics of anatomical systems depicted with XR models. Results: Developmental defects in Preparation 296 include duplicated supradiaphragmatic structures and abnormal osteological features. Subdiaphragmatically, the gut is continuous on the right, but terminates at the distal esophagus on the left. One large liver occupies the abdomen with one spleen located on the left side. Observations suggest duplication of the primitive streak and separate notochords rostrally. Duplication occurs near the yolk sac and involves midgut formation while secondary midline fusion of the upper extremities and ribs likely results from the proximity of the embryos during development. Medical students access the model with device agnostic software during the curricular topic "Human Body Plan" that includes embryology concepts covering mechanisms of twinning. Conclusions: The workflow enables ease-of-access XR visualizations of an old and rare museum specimen. This study also demonstrates digital distribution and utilization of XR models applicable to embryology education.

19.
ACS Appl Mater Interfaces ; 14(38): 43637-43645, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36124874

ABSTRACT

The development of a high-performance ethane (C2H6)-selective adsorbent for the separation of ethane/ethylene (C2H6/C2H4) gas mixtures has been investigated for high-efficiency adsorption-based gas separation. Herein, we investigated Al-based metal-organic frameworks (MOFs) to identify an efficient C2H6-selective adsorbent (CAU-11), supported by a computational simulation study. CAU-11 exhibited numerous advantageous properties (such as low material cost, structural robustness, high reaction yield, and high C2H6/C2H4 selectivity) compared to other Al-based MOFs, indicating immense potential as a C2H6-selective adsorbent. CAU-11 exhibited preferential C2H6 adsorption in single-component gas adsorption experiments, and its predicted ideal adsorption solution theory selectivity of C2H6/C2H4 was over 2.1, consistent with the simulation analysis. Dynamic breakthrough experiments using representative compositions of the C2H6/C2H4 gas mixture confirmed the excellent separation ability of CAU-11; it produced high-purity C2H4 (>99.95%) with productivity values of 0.79 and 2.02 mol L-1 while repeating the cyclic experiment with 1:1 and 1:15 v/v C2H6/C2H4 gas mixtures, respectively, at 298 K and 1 bar. The high C2H6/C2H4 separation ability of CAU-11 could be attributed to its non-polar pore environment and optimum pore dimensions which strengthen the interaction of its pores (via C-H···π interactions) with C2H6 to a greater extent than with C2H4.

20.
Adv Sci (Weinh) ; 9(22): e2201494, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35666071

ABSTRACT

Zeolites and metal-organic frameworks (MOFs) are considered as "competitors" for new separation processes. The production of high-quality gasoline is currently achieved through the total isomerization process that separates pentane and hexane isomers while not reaching the ultimate goal of a research octane number (RON) higher than 92. This work demonstrates how a synergistic action of the zeolite 5A and the MIL-160(Al) MOF leads to a novel adsorptive process for octane upgrading of gasoline through an efficient separation of isomers. This innovative mixed-bed adsorbent strategy encompasses a thermodynamically driven separation of hexane isomers according to the degree of branching by MIL-160(Al) coupled to a steric rejection of linear isomers by the molecular sieve zeolite 5A. Their adsorptive separation ability is further evaluated under real conditions by sorption breakthrough and continuous cyclic experiments with a mixed bed of shaped adsorbents. Remarkably, at the industrially relevant temperature of 423 K, an ideal sorption hierarchy of low RON over high RON alkanes is achieved, i.e., n-hexane ≫ n-pentane ≫ 2-methylpentane > 3-methylpentane ⋙ 2,3-dimethylbutane > isopentane ≈ 2,2-dimethylbutane, together with a productivity of 1.14 mol dm-3 and a high RON of 92, which is a leap-forward compared with existing processes.

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