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1.
Micromachines (Basel) ; 15(8)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39203586

RESUMEN

This paper introduces a cost-effective, high-performance approach to achieving wafer level vacuum packaging (WLVP) for MEMS-based uncooled infrared sensors. Reliable and hermetic packages for MEMS devices are achieved using a cap wafer that is formed using two silicon wafers, where one wafer has precise grating/moth-eye structures on both sides of a double-sided polished wafer for improved transmission of over 80% in the long-wave infrared (LWIR) wavelength region without the need for an AR coating, while the other wafer is used to form a cavity. The two wafers are bonded using Au-In transient liquid phase (TLP) bonding at low temperature to form the cap wafer, which is then bondelectrical and Electronics d to the sensor wafer using glass frit bonding at high temperature to activate the getter inside the cavity region. The bond quality is assessed using three methods, including He-leak tests, cap deflection, and Pirani vacuum gauges. Hermeticity is confirmed through He-leak tests according to MIL-STD 883, yielding values as low as 0.1 × 10-9 atm·cc/s. The average shear strength is measured as 23.38 MPa. The package pressure varies from 133-533 Pa without the getter usage to as low as 0.13 Pa with the getter usage.

2.
Environ Sci Pollut Res Int ; 30(9): 24120-24131, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36333634

RESUMEN

The novel porous nanocomposite sorbent was synthesized by the condensation of the diol monomer with the alkoxysilane cross-linker at moderately high temperatures in the presence of nano-CaCO3 particles. The structural, thermal, and morphological properties of the nanocomposite sorbents were determined by using Fourier transform infrared spectroscopy (FTIR), solid-state CPMAS 13C and 29Si NMR, scanning electron microscope (SEM), and thermal gravimetric analysis (TGA). Adding nano-CaCO3 to the network structure of the polymer not only provided pores to the sorbent but also enhanced its sorption capacity towards various oils and toxic organic solvents. The nanocomposite sorbent exhibited excellent absorption capacity for different toxic organic solvents and oils and great reusability for ten cycles. Moreover, the obtained sorbent material selectively absorbed organic liquids from the surface and bottom of the water without any capacity change owing to their hydrophobicity and oleophilicity. These features of the nanocomposite make it a potential sorbent for the cleaning of oils and oil derivative organic contaminants from the environment.


Asunto(s)
Nanocompuestos , Contaminación por Petróleo , Contaminantes Químicos del Agua , Porosidad , Adsorción , Contaminantes Químicos del Agua/análisis , Aceites/química , Solventes/química
3.
Ann Clin Transl Neurol ; 8(1): 177-189, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33263942

RESUMEN

OBJECTIVE: Transsylvian selective amygdalo-hippocampectomy (tsSAHE) represents a generally recognized surgical procedure for drug-resistant mesial temporal lobe epilepsy (mTLE). Although postoperative seizure freedom can be achieved in about 70% of tsSAHE, there is a considerable amount of patients with persisting postoperative seizures. This might partly be explained by differing extents of resection of various tsSAHE target volumes. In this study we analyzed the resected proportions of hippocampus, amygdala as well as piriform cortex in regard of postoperative seizure outcome. METHODS: Between 2012 and 2017, 82 of 103 patients with mTLE who underwent tsSAHE at the authors' institution were included in the analysis. Resected proportions of hippocampus, amygdala and temporal piriform cortex as target structures of tsSAHE were volumetrically assessed and stratified according to favorable (International League Against Epilepsy (ILAE) class 1) and unfavorable (ILAE class 2-6) seizure outcome. RESULTS: Patients with favorable seizure outcome revealed a significantly larger proportion of resected temporal piriform cortex volumes compared to patients with unfavorable seizure outcome (median resected proportional volumes were 51% (IQR 42-61) versus (vs.) 13 (IQR 11-18), P = 0.0001). Resected proportions of hippocampus and amygdala did not significantly differ for these groups (hippocampus: 81% (IQR 73-88) vs. 80% (IQR 74-92) (P = 0.7); amygdala: 100% (IQR 100-100) vs. 100% (IQR 100-100) (P = 0.7)). INTERPRETATION: These results strongly suggest temporal piriform cortex to constitute a key target resection volume to achieve seizure freedom following tsSAHE.


Asunto(s)
Epilepsia del Lóbulo Temporal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Corteza Piriforme/cirugía , Resultado del Tratamiento , Adulto , Amígdala del Cerebelo/cirugía , Epilepsia Refractaria/cirugía , Femenino , Hipocampo/cirugía , Humanos , Masculino , Persona de Mediana Edad
4.
Chem Biol Drug Des ; 96(1): 684-700, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32691963

RESUMEN

The mouse double minute 2 (MDM2) protein acts as a negative regulator of the p53 tumor suppressor. It directly binds to the N terminus of p53 and promotes p53 ubiquitination and degradation. Since the most common p53-suppressing mechanisms involve the MDM2, proposing novel inhibitors has been the focus of many in silico and also experimental studies. Thus, here we screened around 500,000 small organic molecules from Enamine database at the binding pocket of this oncogenic target. The screening was achieved systematically with starting from the high-throughput virtual screening method followed by more sophisticated docking approaches. The initial high number of screened molecules was reduced to 100 hits which then were studied extensively for their therapeutic activity and pharmacokinetic properties using binary QSAR models. The structural and dynamical profiles of the selected molecules at the binding pocket of the target were studied thoroughly by all-atom molecular dynamics simulations. The free energy of the binding of the hit molecules was estimated by the MM/GBSA method. Based on docking simulations, binary QSAR model results, and free energy calculations, 11 compounds (E1-E11) were selected for in vitro studies. HUVEC vascular endothelium, colon cancer, and breast cancer cell lines were used for testing the binding affinities of the identified hits and for further cellular effects on human cancer cell. Based on in vitro studies, six compounds (E1, E2, E5, E6, E9, and E11) in breast cancer cell lines and six compounds (E1, E2, E5, E6, E8, and E10) in colon cancer cell lines were found as active. Our results showed that these compounds inhibit proliferation and lead to apoptosis.


Asunto(s)
Antineoplásicos/química , Inhibidores Enzimáticos/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Ratones , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , Conformación Proteica , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Relación Estructura-Actividad Cuantitativa , Bibliotecas de Moléculas Pequeñas/farmacocinética
5.
BMC Neurol ; 18(1): 3, 2018 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-29316893

RESUMEN

BACKGROUND: Spinocerebellar ataxia (SCA) subtypes are often caused by expansions in non-coding regions of genes like SCA8, SCA10, SCA12 and SCA36. Other ataxias are known to be associated with repeat expansions such as fragile X-associated tremor ataxia syndrome (FXTAS) or expansions in the C9orf72 gene. When no mutation has been identified in the aforementioned genes next-generation sequencing (NGS)-based diagnostics may also be applied. In order to define an optimal diagnostic strategy, more information about the frequency and phenotypic characteristics of rare repeat expansion disorders associated with ataxia should be at hand. METHODS: We analyzed a consecutive cohort of 440 German unrelated patients with symptoms of cerebellar ataxia, dysarthria and other unspecific symptoms who were referred to our center for SCA diagnostics. They showed alleles in the normal range for the most common SCA subtypes SCA1-3, SCA6, SCA7 and SCA17. These patients were screened for expansions causing SCA8, SCA10, SCA12, SCA36 and FXTAS as well as for the pathogenic hexanucleotide repeat in the C9orf72 gene. RESULTS: Expanded repeats for SCA10, SCA12 or SCA36 were not identified in the analyzed patients. Five patients showed expanded SCA8 CTA/CTG alleles with 92-129 repeats. One 51-year-old male with unclear dementia symptoms was diagnosed with a large GGGGCC repeat expansion in C9orf72. The analysis of the fragile X mental retardation 1 gene (FMR1) revealed one patient with a premutation (>50 CGG repeats) and seven patients with alleles in the grey zone (41 to 54 CGG repeats). CONCLUSIONS: Altogether five patients showed 92 or more SCA8 CTA/CTG combined repeats. Our results support the assumption that smaller FMR1 gene expansions could be associated with the risk of developing neurological signs. The results do not support genetic testing for C9orf72 expansion in ataxia patients.


Asunto(s)
Ataxia/genética , Proteína C9orf72/genética , Expansión de las Repeticiones de ADN/genética , Síndrome del Cromosoma X Frágil/genética , Proteínas del Tejido Nervioso/genética , Ataxias Espinocerebelosas , Temblor/genética , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ataxias Espinocerebelosas/epidemiología , Ataxias Espinocerebelosas/genética , Adulto Joven
6.
Environ Sci Pollut Res Int ; 23(12): 11695-707, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26939691

RESUMEN

Organic-inorganic hybrid gels were synthesized by the condensation of a linear aliphatic diol (1,8-octanediol) and altering the chain length of the alkyltriethoxysilanes (from ethyltriethoxysilane to hexadecyltrimethoxysilane) through a bulk polymerization process without using any initiator, activator, catalyst, or solvent for the selective removal of oils from water. Fourier transform infrared spectroscopy (FTIR) and solid-state (13)C and (29)Si cross-polarization magic-angle spinning nuclear magnetic resonance (CPMAS NMR) were used for the structural analysis of hybrid gels. Thermal properties of the hybrid gels were determined by thermogravimetric analysis (TGA). Oil absorbency of organic-inorganic hybrid gels was determined by oil absorption tests. The results showed that hybrid gels have high and fast absorption capacities and excellent reusability. Good selectivity, high thermal stability, low density, and excellent recyclability for the oil removal give the material potential applications.


Asunto(s)
Geles/síntesis química , Octanoles/química , Contaminación por Petróleo/prevención & control , Silanos/química , Contaminantes Químicos del Agua/química , Absorción Fisicoquímica , Alcoholes , Espectroscopía de Resonancia Magnética , Aceites/química , Polimerizacion , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Agua
7.
J Hazard Mater ; 309: 210-8, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26894295

RESUMEN

In this study, a series of different molecular weights of poly(tetrahydrofuran) (PTHF), which is one of the most important commercial polymers around the world, was condensed with tris[3-(trimethoxysilyl)propyl]isocyanurate (ICS) to generate a cross-linked 3-dimensional network in order to obtain organic solvent/oil sorbents having high swelling capacity. The prepared sorbents show high and fast swelling capacity in oils such as dichloromethane (DCM), tetrahydrofuran (THF), acetone, t-butyl methyl ether (MTBE), gasoline, euro diesel, and crude oil. The recovery of the absorbed oils from contaminated surfaces, especially from water, and the regeneration of the sorbents after several applications are effective. The characterization and thermal properties of the sorbents are identified by Fourier transform infrared spectroscopy (FTIR), solid-state (13)C and (29)Si cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and thermal gravimetric analyses (TGA), respectively. The new usage area of PTHF is emerged by the preparation of PTHF-based network structure with high oil absorption capacity and having excellent reusability as an oil absorbent for the removal of organic liquids from the spill site.

8.
Mar Pollut Bull ; 96(1-2): 155-64, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26002096

RESUMEN

In this study, reusable poly(alkoxysilane) organogels with high absorption capacities were synthesized by the condensation of a cyclo aliphatic glycol (UNOXOL™) and altering the chain length of the alkyltriethoxysilanes. The structural and thermal properties of cross-linked poly(alkoxysilane) polymers were determined by FTIR, solid-state (13)C and (29)Si CPMAS NMR and TGA. The oil absorbency of poly(alkoxysilane)s was determined through oil absorption tests, absorption and desorption kinetics. Results showed that the highest oil absorbency capacities were found to be 295% for hexane, 389% for euro diesel, 428% for crude oil, 652% for gasoline, 792% for benzene, 792% for toluene, 868% for tetrahydrofuran, and 1060% for dichloromethane for the poly(alkoxysilane) gels based on UNOXOL™ and dodecyltriethoxysilane. Owing to their hydrophobic structure, the poly(alkoxysilane) organogels can selectively absorb crude oil from water. The reusability of the absorbents was quantitatively investigated, demonstrating that absorbents can be used effectively at least nine times.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Petróleo , Polímeros/química , Contaminantes Químicos del Agua/química , Adsorción , Gasolina , Interacciones Hidrofóbicas e Hidrofílicas , Contaminación por Petróleo/estadística & datos numéricos , Contaminantes Químicos del Agua/análisis
9.
J Environ Manage ; 149: 57-64, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25463571

RESUMEN

Novel poly(alkoxysilane)s with high oil and organic solvent absorbencies were prepared by a bulk polymerization technique via the condensation of 1,3-benzenedimethanol with different lengths of alkoxysilanes at 160 °C without using a catalyst. The influence of the length of the alkoxysilane on the polymer properties and swelling ratios was investigated. Swelling experiments in various solvents indicated that these cross-linked poly(alkoxysilane)s can be used as absorbents for oils and oil-derived organic solvents. The swelling features of the poly(alkoxysilane)s were determined by solvent absorption tests, swelling kinetics experiments, and desorption kinetics measurements. The absorption capacities of the poly(alkoxysilane)s were 50-725% for various organic solvents and oil derivatives such as gasoline and diesel. The structural and thermal properties of the cross-linked poly(alkoxysilane) polymers were determined by FTIR, solid-state (13)C and (29)Si cross-polarization magic angle spinning (CP-MAS) NMR, and thermal gravimetric analysis (TGA).


Asunto(s)
Restauración y Remediación Ambiental/métodos , Geles/química , Aceites/aislamiento & purificación , Silanos/química , Solventes/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Alcoholes/química , Espectroscopía de Resonancia Magnética/métodos , Aceites/química , Polímeros/química , Solventes/química , Contaminantes Químicos del Agua/análisis
10.
J Enzyme Inhib Med Chem ; 28(4): 870-5, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22803662

RESUMEN

A series of some 4-(aza substituted) methylene substituted dihydroxy coumarines were evaluated for their antioxidant and antielastase activities. Different in vitro methodologies such as total reducing power, 1,1-diphenyl-2-picryl-hydrazil (DPPH·) free radical scavenging, ABTS radical scavenging activity were used as antioxidant activity. All the tested compounds exhibited potent free radical scavenging ability and antielastase activites.


Asunto(s)
Antioxidantes/síntesis química , Antioxidantes/farmacología , Cumarinas/química , Cumarinas/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Elastasa Pancreática/antagonistas & inhibidores , Antioxidantes/química , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Humanos , Estructura Molecular , Elastasa Pancreática/metabolismo , Relación Estructura-Actividad
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