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Low-cost, highly efficient thermoelectric thin-film materials are becoming increasingly popular as miniaturization progresses. Mg3Sb2has great potential due to its low cost and high performance. However, the fabrication of Mg3Sb2thin films with high power factors (PFs) poses a certain challenge. In this work, we propose a general approach to prepare Mg3Sb2thin films with excellent thermoelectric properties. Using a two-step thermal evaporation and rapid annealing process, (001)-oriented Mg3Sb2thin films are fabricated onc-plane-oriented Al2O3substrates. The structure of the film orientation is optimized by controlling the film thickness, which modulates the thermoelectric performance. The PF of the Mg3Sb2at 500 nm (14µW·m-1·K-2) would increase to 169µW·m-1·K-2with Ag doping (Mg3Ag0.02Sb2) at room temperature. This work provides a new strategy for the development of high-performance thermoelectric thin films at room temperature.
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BACKGROUND: Flow diverter devices are increasingly used for endovascular treatment of internal carotid artery aneurysms. Treatment of ophthalmic segment aneurysms with flow diverter devices also includes coverage of the ophthalmic artery but may result in complications. It is unclear, however, whether these devices mechanically block blood flow in the ophthalmic artery. Also unclear is the relationship between deployment of a flow diverter device and post-treatment occlusion. We studied hemodynamic changes in the ophthalmic artery after deployment of a flow diverter device to determine the relationship between those changes and post-stent occlusion of the artery. METHODS: We analyzed hemodynamic modifications in the ophthalmic artery in 21 patients (19 women, 2 men; mean age 53.43 ± 7.32 years) treated by a single pipeline embolization device. Patient-specific geometries were determined from three-dimensional digital subtraction angiography and the stenting process was simulated. Computational fluid dynamics technology was used to analyze the change in ophthalmic artery hemodynamics. We compared pre-treatment and post-treatment flow velocity of the ophthalmic artery. RESULTS: Among the 21 patients with aneurysms located in the ophthalmic segment, no ophthalmic artery occlusion was found during immediate or follow-up angiography. Post-stent flow velocity in the ophthalmic artery decreased from 0.35 ± 0.19 to 0.33 ± 0.20 m/s, with the difference not being statistically significant (P = 0.106). CONCLUSION: Our results showed no significant change in ophthalmic artery blood flow after pipeline embolization device deployment. Hence, post-stent occlusion of the ophthalmic artery could not be explained by reduced blood flow. Delayed thrombosis and neointimal formation maybe the keys to ophthalmic artery occlusion and need further investigation.
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Prótesis Vascular , Hemorreología/fisiología , Arteria Oftálmica/fisiopatología , Velocidad del Flujo Sanguíneo , Embolización Terapéutica , Femenino , Humanos , Aneurisma Intracraneal/fisiopatología , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: A nearly complete hominin fossil cranium from Dali in Shaanxi Province, China was excavated in 1978. We update and expand on previous research by providing a multivariate analysis of the specimen relative to a large sample of Middle and Late Pleistocene hominins. MATERIALS AND METHODS: We apply principal components analysis, discriminant function analysis, and a method of assessing group membership based on a soft independent model of class analogy (SIMCA) to the study of Dali's cranial morphology. We evaluate Dali's affinities within the context of Middle and Late Pleistocene Homo patterns of craniofacial morphology. RESULTS: When just the facial skeleton is considered, Dali aligns with Middle Paleolithic H. sapiens and is clearly more derived than African or Eurasian Middle Pleistocene Homo. When just the neurocranium is considered, Dali is most similar to African and Eastern Eurasian but not Western European Middle Pleistocene Homo. When both sets of variables are considered together, Dali exhibits a unique morphology that is most closely aligned with the earliest H. sapiens from North Africa and the Levant. DISCUSSION: These results add perspective to our previous view of as Dali a "transitional" form between Chinese H. erectus and H. sapiens. Athough no taxonomic allocation is appropriate at this time for Dali, it appears to represent a population that played a more central role in the origin of Chinese H. sapiens. Dali's affinities can be understood in the context of Wu's Continuity with Hybridization scenario and a braided-stream network model of gene flow. Specifically, we propose that Pleistocene populations in China were shaped by periods of isolated evolutionary change within local lineages at certain times, and gene flow between local lineages or between Eastern and Western Eurasia, and Africa at other times, resulting in contributions being made in different capacities to different regions at different times.
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Evolución Biológica , Hominidae/anatomía & histología , Cráneo/anatomía & histología , África , Animales , Antropología Física , China , Fósiles , Flujo Génico , Hominidae/genética , Análisis MultivarianteRESUMEN
Size-dependent nonlinear optical properties of modification-free transition metal dichalcogenide (TMD) nanosheets are reported, including MoS2 , WS2 , and NbSe2 . Firstly, a gradient centrifugation method is demonstrated to separate the TMD nanosheets into different sizes. The successful size separation allows the study of size-dependent nonlinear optical properties of nanoscale TMD materials for the first time. Z-scan measurements indicate that the dispersion of MoS2 and WS2 nanosheets that are 50-60 nm thick leads to reverse saturable absorption (RSA), which is in contrast to the saturable absorption (SA) seen in the thicker samples. Moreover, the NbSe2 nanosheets show no size-dependent effects because of their metallic nature. The mechanism behind the size-dependent nonlinear optical properties of the semiconductive TMD nanosheets is revealed by transient transmission spectra measurements.
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The Hexian calvarium is one of the most complete and well-preserved Homo erectus fossils ever found in east Asia, apart from the Zhoukoudian specimens. Various methods bracket the age of the Hexian fossil to between 150 and 412 ka (thousands of years ago). The Hexian calvarium has been considered to be H. erectus given its morphological similarities to Zhoukoudian and Javan H. erectus. However, discussion continues regarding the affinities of the Hexian specimen with other H. erectus fossils. The arguments mainly focus on its relationships to other Asian H. erectus fossils, including those from both China and Java. To better determine the affinities of the Hexian cranium, our study used 3D landmark and semilandmark geometric morphometric techniques and multivariate statistical analyses to quantify the shape of the neurocranium and to compare the Hexian cranium to other H. erectus specimens. The results of this study confirmed the morphological similarities between Hexian and Chinese H. erectus in overall morphology, and particularly in the structure of the frontal bone and the posterior part of the neurocranium. Although the Hexian specimen shows the strongest connection to Chinese H. erectus, the morphology of the lateral neurocranium resembles early Indonesian H. erectus specimens, possibly suggesting shared common ancestry or gene flow from early Indonesian populations. Overall cranial and frontal bone morphology are strongly influenced by geography. Although geographically intermediate between Zhoukoudian and Indonesian H. erectus, the Hexian specimen does not form part of an obvious morphological gradient with regard to overall cranial shape.
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Evolución Biológica , Fósiles/anatomía & histología , Hominidae/anatomía & histología , Cráneo/anatomía & histología , Animales , Cefalometría , China , Hominidae/clasificación , Masculino , FilogeniaRESUMEN
AIMS: A bone-invasive pituitary adenoma exhibits aggressive behavior, leading to a worse prognosis. We have found that TNF-α promotes bone invasion by facilitating the differentiation of osteoclasts, however, before bone-invasive pituitary adenoma invades bone tissue, it needs to penetrate the dura mater, and this mechanism is not yet clear. METHODS: We performed transcriptome microarrays on specimens of bone-invasive pituitary adenomas (BIPAs) and noninvasive pituitary adenomas (NIPAs) and conducted differential expressed gene analysis and enrichment analysis. We altered the expression of TNF-α through plasmids, then validated the effects of TNF-α on GH3 cells and verified the efficacy of the TNF-α inhibitor SPD304. Finally, the effects of TNF-α were validated in in vivo experiments. RESULTS: Pathway act work showed that the MAPK pathway was significantly implicated in the pathway network. The expression of TNF-α, MMP9, and p-p38 is higher in BIPAs than in NIPAs. Overexpression of TNF-α elevated the expression of MAPK pathway proteins and MMP9 in GH3 cells, as well as promoted proliferation, migration, and invasion of GH3 cells. Flow cytometry indicated that TNF-α overexpression increased the G2 phase ratio in GH3 cells and inhibited apoptosis. The expression of MMP9 was reduced after blocking the P38 MAPK pathway; overexpression of MMP9 promoted invasion of GH3 cells. In vivo experiments confirm that the TNF-α overexpression group has larger tumor volumes. SPD304 was able to suppress the effects caused by TNF-α overexpression. CONCLUSION: Bone-invasive pituitary adenoma secretes higher levels of TNF-α, which then acts on itself in an autocrine manner, activating the MAPK pathway and promoting the expression of MMP9, thereby accelerating the membrane invasion process. SPD304 significantly inhibits the effect of TNF-α and may be applied in the clinical treatment of bone-invasive pituitary adenoma.
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Adenoma , Sistema de Señalización de MAP Quinasas , Metaloproteinasa 9 de la Matriz , Invasividad Neoplásica , Neoplasias Hipofisarias , Factor de Necrosis Tumoral alfa , Factor de Necrosis Tumoral alfa/metabolismo , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Humanos , Adenoma/patología , Adenoma/metabolismo , Animales , Metaloproteinasa 9 de la Matriz/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Línea Celular Tumoral , Femenino , Ratones , Ratones Desnudos , Comunicación Autocrina/fisiología , Comunicación Autocrina/efectos de los fármacos , Persona de Mediana Edad , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Adulto , Ratas , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Transducción de Señal/fisiología , Transducción de Señal/efectos de los fármacosRESUMEN
Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonate)) thin film by using photochromic diarylethene (DAE) dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 µV K-1 to 135.4 µV K-1 and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 µW m-1 K-2 from an original value of 6.78 µW m-1 K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.
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BACKGROUND: Studies reporting spontaneous delayed migration or shortening (SDMS) after treatment with the Pipeline Embolization Device (PED) are limited. This study aimed to evaluate the incidence of SDMS after PED treatment, propose management strategies, and identify the risk factors contributing to its occurrence. METHODS: We retrospectively reviewed consecutive patients with an intracranial aneurysm (IA) treated with PEDs at three institutions. SDMS was classified as type I or II based on whether the PED covered the aneurysm neck. RESULTS: The total cohort comprised 790 patients. SDMS was identified in 24 (3.04%) patients. Eighteen of the 24 patients had type I SDMS and did not require retreatment, while the remaining six patients had type II SDMS and all received retreatment. Multivariate logistic regression showed that the difference between the proximal and distal parent artery diameters (DPAD) (adjusted OR 2.977; 95% CI 1.054 to 8.405; P=0.039) and device tortuosity index (DTI) (adjusted OR 8.059; 95% CI 2.867 to 23.428; P<0.001) were independent predictors of SDMS after PED treatment, while the difference in length (DL) (adjusted OR 0.841; 95% CI 0.738 to 0.958; P=0.009) and PED plus coiling (adjusted OR 0.288; 95% CI 0.106 to 0.785; P=0.015) were protective factors. CONCLUSION: The incidence of SDMS after PED treatment of IA was 3.04%. For patients with type I SDMS with incomplete aneurysm occlusion we recommend continuous imaging follow-up while, for patients with type II SDMS, we recommend aggressive retreatment. The DPAD and DTI were independent risk predictors of SDMS after PED treatment, while the DL and PED plus coiling were protective factors.
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OBJECTIVE: Pipeline embolization device (PED) placement for the treatment of intracranial aneurysms is safe and effective under general anesthesia (GA). However, GA is associated with certain risks, longer procedural time, and higher hospital cost. The authors aimed to compare clinical outcomes and hospital cost between GA and local anesthesia (LA) procedures in patients who underwent PED placement for intracranial aneurysm treatment. METHODS: This retrospective study analyzed the charts of 216 patients with 223 intracranial aneurysms treated using the PED from June 2022 to March 2023. Cases were grouped according to type of anesthesia administered (LA or GA). Propensity score matching (PSM) was used to balance the groups to minimize confounding bias. RESULTS: Eighty-four patients with 88 aneurysms were treated under LA, and 132 patients with 135 aneurysms were treated under GA. The complication rate and modified Rankin Scale score at 6 months were similar in both groups. Procedural time was significantly shorter with LA both before (87.47 ± 22.68 minutes vs 118.90 ± 46.80 minutes, p < 0.001) and after (84.75 ± 16.77 minutes vs 110.02 ± 38.56 minutes, p < 0.001) PSM. LA eliminates the need for postanesthesia recovery. Hospital cost was significantly lower in the LA group both before ($30,820.74 ± $3216.93 vs $32,846.62 ± $4731.50, p = 0.001) and after ($30,127.83 ± $2763.12 vs $33,874.41 ± $3163.56, p = 0.002) PSM. CONCLUSIONS: PED placement under LA can achieve satisfactory outcomes similar to those of PED placement under GA; however, the use of LA reduces procedural time and hospital cost.
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In 1978, a nearly complete hominin fossil cranium was recovered from loess deposits at the site of Dali in Shaanxi Province, northwestern China. It was subsequently briefly described in both English and Chinese publications. Here we present a comprehensive univariate and nonmetric description of the specimen and provide comparisons with key Middle Pleistocene Homo erectus and non-erectus hominins from Eurasia and Africa. In both respects we find affinities with Chinese H. erectus as well as African and European Middle Pleistocene hominins typically referred to as Homo heidelbergensis. Specifically, the Dali specimen possesses a low cranial height, relatively short and arched parietal bones, an angled occipital bone, and a nonprominent articular tubercle relative to the preglenoid surface all of which distinguish it from Afro/European Middle Pleistocene Homo and align it with Asian H. erectus. At the same time, it displays a more derived morphology of the supraorbital torus and supratoral sulcus and a thinner tympanic plate than H. erectus, a relatively long upper (lambda-inion) occipital plane with a clear separation of inion and opisthocranion, and an absolute and relative increase in brain size, all of which align it with African and European Middle Pleistocene Homo. Finally, traits such as the form of the frontal keel and the relatively short, broad midface align Dali specifically with other Chinese specimens from the Middle Pleistocene and Late Pleistocene, including H. erectus, and differentiate these from the Afro/European specimens of this time period.
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Fósiles , Hominidae/anatomía & histología , Cráneo/anatomía & histología , Animales , Antropología Física , China , Paleopatología , Cráneo/patologíaRESUMEN
The 2007 discovery of fragmentary human remains (two molars and an anterior mandible) at Zhirendong (Zhiren Cave) in South China provides insight in the processes involved in the establishment of modern humans in eastern Eurasia. The human remains are securely dated by U-series on overlying flowstones and a rich associated faunal sample to the initial Late Pleistocene, >100 kya. As such, they are the oldest modern human fossils in East Asia and predate by >60,000 y the oldest previously known modern human remains in the region. The Zhiren 3 mandible in particular presents derived modern human anterior symphyseal morphology, with a projecting tuber symphyseos, distinct mental fossae, modest lateral tubercles, and a vertical symphysis; it is separate from any known late archaic human mandible. However, it also exhibits a lingual symphyseal morphology and corpus robustness that place it close to later Pleistocene archaic humans. The age and morphology of the Zhiren Cave human remains support a modern human emergence scenario for East Asia involving dispersal with assimilation or populational continuity with gene flow. It also places the Late Pleistocene Asian emergence of modern humans in a pre-Upper Paleolithic context and raises issues concerning the long-term Late Pleistocene coexistence of late archaic and early modern humans across Eurasia.
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Fósiles , Paleodontología/métodos , China , Asia Oriental , Humanos , Mandíbula , Diente MolarRESUMEN
The thermoelectric figure of merit ZT bridges the efficiency and material parameters for a thermoelectric device operating under constant temperature of the hot- and cold-source thermal boundary (Type-I TB). However, many application scenarios fall under the constant heat-in flux (qh ) and constant cold-source temperature (Tc ) thermal boundary (Type-II TB), for which a figure of merit is absent for more than half a century. This study aims to fill this gap and propose a figure of merit ZQD for the thermoelectric devices under the Type-II TB condition, defined as Z Q D = ( Z T c Z T c + 1 ) ( h κ ) ( q h T c ) $Z{Q}_{\mathrm{D}} = ( {\frac{{Z{T}_{\mathrm{c}}}}{{Z{T}_{\mathrm{c}} + 1}}} )( {\frac{h}{\kappa }} )( {\frac{{{q}_{\mathrm{h}}}}{{{T}_{\mathrm{c}}}}} )$ , where Z, h, and κ are the traditional figure of merit, leg height, and thermal conductivity, respectively. The effectiveness of ZQD is verified through both numerical calculations and experiments, which are more accurate and practical than ZT. Furthermore, a system-level figure of merit ZQS is suggested after considering the external thermal resistance. Finally, optimization strategies for thermoelectric systems based on ZQS are proposed, showing a 30% enhancement in the efficiency. ZQD and ZQS are expected to be widely used in the thermoelectric field.
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Nano approaches are practical strategies to boost the thermoelectric figure of merit due to the strong phonon scattering from the grain boundaries and nanoinclusions. Here, we have reported a strong phonon scattering at the heterogeneous interfaces of Mg2Sn/Mg3Sb2 high-content nanocomposites (HCnCs). As a result, a significantly reduced lattice thermal conductivity of 1.09 W m-1 K-1 was observed in the equimolar Mg2Sn/Mg3Sb2 HCnC, 80% lower than pure Mg2Sn and 25% lower than pure Mg3Sb2. As a result, a high ZT â¼ 1.13 at 773 K was achieved in the Mg2Sn/Mg3Sb2 HCnC. Furthermore, various defects, including solid solutions, nanoinclusions, and misfit dislocations, were observed in both the Mg3Sb2 phase and the Mg2Sn phase through the microstructure characterization.
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BACKGROUND: Brain arteriovenous malformation (BAVM) is a main cause of cerebral hemorrhage and hemorrhagic stroke in adolescents. Morphologically, a BAVM is an abnormal connection between cerebrovascular arteries and veins. The genetic etiology of BAVMs has not been fully elucidated. In this study, we aim to investigate potential recessive genetic variants in BAVMs by interrogation of rare compound heterozygous variants. METHODS: We performed whole exome sequencing (WES) on 112 BAVM trios and analyzed the data for rare and deleterious compound heterozygous mutations associated with the disease. RESULTS: We identified 16 genes with compound heterozygous variants that were recurrent in more than one trio. Two genes (LRP2, MUC5B) were recurrently mutated in three trios. LRP2 has been previously associated with BAVM pathogenesis. Fourteen genes (MYLK, HSPG2, PEAK1, PIEZO1, PRUNE2, DNAH14, DNAH5, FCGBP, HERC2, HMCN1, MYH1, NHSL1, PLEC, RP1L1) were recurrently mutated in two trios, and five of these genes (MYLK, HSPG2, PEAK1, PIEZO1, PRUNE2) have been reported to play a role in angiogenesis or vascular diseases. Additionally, abnormal expression of the MYLK protein is related to spinal arteriovenous malformations. CONCLUSION: Our study indicates that rare recessive compound heterozygous variants may underlie cases of BAVM. These findings improve our understanding of BAVM pathology and indicate genes for functional validation.
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Fístula Arteriovenosa/genética , Secuenciación del Exoma/métodos , Exoma/genética , Variación Genética/genética , Malformaciones Arteriovenosas Intracraneales/genética , Adolescente , Adulto , Fístula Arteriovenosa/epidemiología , China/epidemiología , Proteínas del Ojo/genética , Femenino , Humanos , Malformaciones Arteriovenosas Intracraneales/epidemiología , Masculino , Adulto JovenRESUMEN
Objective: To evaluate effectiveness and safety of Pipeline embolization device (PED) for large or giant verterbrobasilar aneurysms (LGVBAs), and to compare the therapeutic effects of PED with and without adjunctive coils. Methods: We retrospectively analyzed 21 cases of unruptured LGVBAs who were treated in our hospital with PED. These cases were divided into "PED group" and "PED with adjunctive coils group." We compared the aneurysm characteristics and treatment outcomes between the two groups. Results: The overall neurological complication rate was 28.6% (6/21) and the mortality rate was 4.8% (1/21). There were 12 patients in the PED group and nine in the PED with adjunctive coils group. There were no significant differences in age, smoking, hypertension, aneurysm size, aneurysm location, or operation time between the two groups. The complete aneurysm embolization rate and favorable outcome rate (modified Rankin Scale = 0,1) of the PED with adjunctive coils group was 78% (7/9) and 100% (9/9), respectively, which were both better compared with the PED group with 63.6% (7/11) and 83% (10/12), respectively. However, these differences were not statistically significant. Conclusion: The effectiveness and safety of PED for LGVBAs is acceptable. Treatment results did not differ between the PED and PED with adjunctive coils groups; therefore, whether coils should be used may depend the operator. Our results suggest that correct use of the coils does not increase complications. We suggest that PED with adjunctive coils should be used for some selected LGVBAs.
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Objective: To investigate the safety and efficacy of low-profile visualized intraluminal support (LVIS) stent-assisted coiling of intracranial tiny aneurysms using a "compressed" stent technique. Methods: We retrospectively analyzed patients with tiny aneurysms treated in our hospital with LVIS devices using a compressed stent technique. We analyzed patients' imaging outcomes, clinical outcomes, and complications. Results: Forty-two tiny aneurysms in 42 patients were included in this study cohort; 8 patients presented with subarachnoid hemorrhage at admission. The immediate postoperative complete embolization rate was 76.2% (32/42). After an average of 8.5 months of imaging follow-up, the complete embolization rate was 90.5% (38/42), and no aneurysm recanalization occurred. After an average of 24.4 months of clinical follow-up, 95.2% (40/42) of the patients achieved favorable clinical outcomes (modified Rankin scale = 0/1). Operation-related complications occurred in two patients (4.8%); one intraoperative acute thrombosis, and one significant unilateral decreased vision during the postoperative follow-up. Conclusion: LVIS stent-assisted coiling of intracranial tiny aneurysms using a compressed stent technique is safe and effective. Combined stent compression technology is beneficial to maximize the complete embolization of aneurysms and reduce aneurysm recanalization. This study expands the clinical applicability of LVIS stents.
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There is an indirect link between multiple sexual partners (MSP) and cervical intraepithelial neoplasia (CIN) or even cervical cancer (CC). MSP may also lead to bacterial vaginosis (BV). The relationship among MSP, BV, human papillomavirus (HPV) infection and CIN/CC development in Chinese women remains unclear. The present study was designed to clarify their association. The study retrospectively analyzed 549 female patients who had visited a physical examination center. The MSP information was acquired, and vaginal microecology, HPV and cervical conization pathology (CCP) tests were performed when necessary. MSP status was distinct among patients with different levels of BV severity. In addition, as the severity of BV progressed, the HPV-positive ratio increased. Meanwhile, MSP was significantly associated with a positive HPV outcome, including HPV 16, HPV 18 and other high-risk HPV infections. The MSP group had a significantly higher percentage of positive CCP outcomes (particularly cases with CIN-II and CIN-III). Similarly, higher BV severity meant more severe CIN/CC progression. A logistic regression model based on age, MSP status and the Nugent score level was used in order to predict the CCP outcome. Furthermore, a receiver operating characteristic curve analysis resulted in an area under the curve of 0.834. In conclusion, the combination of MSP information and BV examination may provide a rapid, economic and accurate prediction of CIN/CC. Health education on sexual behavior and timely detection/treatment of BV should be conducted to reduce the risk of CC.
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Objective: Pipeline embolization devices (PEDs) are widely used to exclude intracranial aneurysms from their parent arteries. Side branches covered by PEDs, however, sometimes experience occlusion and related symptoms. Thus, predictors of branch occlusion and the patency and clinical outcomes of these branches are concerning. Methods: We conducted a retrospective review of consecutive patients who had been treated with PEDs in our institution during 2015-2018 to identify those in whom one or more branches were involved. Pretreatment and follow-up angiograms were assessed to determine patency of the involved branches. Demographic and clinical data, treatment strategies, and comorbidities were collected to investigate their relations with branch occlusion. Results: Altogether, 173 branches [24 (13.9%) occluded), 29 (16.8%) with diminished flow] in 126 patients were studied. Five patients (OphA involved) presented with blurred vision and 1 patient (ACA involved) presented with headache. None of the other patients had neurologic complications or clinical strokes related to branch occlusion. Multivariate analysis identified that small PED diameter [p = 0.003, odds ratio (OR) = 0.168], branches arising from the aneurysm (p = 0.004, OR = 6.614), and involvement of the anterior cerebral artery (ACA) (p < 0.001, OR = 25.656) significantly predicted branch occlusion. Conclusion: Branch occlusion rate after PED deployment was low and most occlusions was asymptomatic. Branches with rich collateral supply were more likely to occlude, especially the ACA. Smaller PED diameter, branches arising from the aneurysm, and ACA involvement were significant predictors of branch occlusion after PED treatment.
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Objective: Flow diverter devices are increasingly used in the treatment of posterior circulation aneurysms, sometimes necessarily involving ostia of side branches and perforators. The aim of this study was to identify the hemodynamic influence of flow diverters on side branches and perforators of the posterior circulation. Methods: We performed a retrospective study of consecutive patients treated by a flow diverter device for posterior circulation aneurysms with anterior inferior cerebellar artery (AICA) or posterior inferior cerebellar artery (PICA) involvement. Computational fluid dynamics (CFD) were used to discern hemodynamic changes of branches after deployment of the flow diverter. Results: We studied 18 branches from 17 patients (mean age, 50.72 ± 8.17 years). No branches were occluded on immediate angiography and later follow-up. Average flow velocity in aneurysms decreased from 0.077 ± 0.065 m/s to 0.025 ± 0.025 m/s (p < 0.01). Average flow velocity in branch ostia decreased from 0.29 ± 0.14 m/s to 0.27 ± 0.16 m/s (p = 0.189). The difference in flow velocity reduction ratio between aneurysms and branches was statistically significant (68.8 vs. 9.5%; p < 0.001). The mean pressure in branch ostia increased from 10,717.4 ± 489.0 to 10,859.0 ± 643.4 Pa (p < 0.01). Conclusion: While a flow diverter device is capable of slowing down aneurysmal inflow, it is unable to block the flow into branches and perforators when used in the treatment of posterior circulation aneurysms; flow velocity in branches even increased in some cases. With a low branch occlusion ratio, it may be acceptable to cover posterior circulation branches and perforators if unavoidable.
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To date, the earliest modern human fossils found outside of Africa are dated to around 90,000 to 120,000 years ago at the Levantine sites of Skhul and Qafzeh. A maxilla and associated dentition recently discovered at Misliya Cave, Israel, was dated to 177,000 to 194,000 years ago, suggesting that members of the Homo sapiens clade left Africa earlier than previously thought. This finding changes our view on modern human dispersal and is consistent with recent genetic studies, which have posited the possibility of an earlier dispersal of Homo sapiens around 220,000 years ago. The Misliya maxilla is associated with full-fledged Levallois technology in the Levant, suggesting that the emergence of this technology is linked to the appearance of Homo sapiens in the region, as has been documented in Africa.