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1.
Langmuir ; 39(11): 3934-3941, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36883239

RESUMEN

Deicing has significant relevance in various applications such as transportation, energy production, and telecommunication. The use of surface acoustic waves (SAWs) is an attractive option for deicing as it offers several advantages such as localized heating, in situ control, low power, and system integration for highly efficient deicing. Here, we report an understanding of the dynamics of deicing of microlitre volume water droplets (1 to 30 µL) exposed to low power (0.3 W) SAW actuation using an interdigitated electrode on a piezoelectric (LiNbO3) substrate. We study the time variation of the volume of liquid water from the onset of SAW actuation to complete deicing, which takes 2.5 to 35 s depending on the droplet volume. The deicing phenomenon is attributed to acoustothermal heating which is found to be greatly influenced by the loss of ice adhesion with the substrate and the acoustic streaming within the liquid water. Acoustothermal heating inside the droplet is characterized by the temperature distribution inside the droplet using infrared thermography, and acoustic streaming is observed using dye-based optical microscopy. A rapid enhancement in deicing is observed upon the detachment of ice from the substrate and the onset of acoustic streaming, marked by a sudden increase in the liquid water volume, droplet temperature, and heat transfer coefficient. The deicing time is found to increase linearly with droplet volume as observed from experiments and further verified using a theoretical model. Our study provides an improved understanding of the recently introduced SAW-based deicing technique that may open up the avenue for a suitable alternative to standard deicing protocols.

2.
Langmuir ; 38(15): 4763-4773, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35395155

RESUMEN

Microwell arrays are ideal platforms for cell culturing, cell separation, and low-volume liquid handling. The ability to manipulate droplets in microwells could open up the opportunity for developing new biochemical assays. Here, we study the trapping of aqueous droplets in an oil-filled microwell driven by the application of nanometer amplitude vibrations called surface acoustic waves (SAW). We elucidate the dynamics of the droplet within the vortex toward the final trapping location and the physics of the trapping phenomenon using a theoretical model by considering the relevant forces. Our study revealed that the combined effect of acoustic radiation and hydrodynamic forces leads to droplet migration and trapping. We demarcate the trapping and nontrapping regimes in terms of the minimum critical input power required for the trapping of droplets of different sizes and densities. We find that the critical power varies as the square of the droplet size and is higher for a denser droplet. The effects of input power and droplet size on the trapping location and trapping time are also studied.


Asunto(s)
Hidrodinámica , Sonido , Modelos Teóricos , Vibración , Agua
3.
Langmuir ; 37(4): 1578-1587, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33478219

RESUMEN

Microwell arrays are amongst the most commonly used platforms for biochemical assays. However, the coalescence of droplets that constitute the dispersed phase of suspensions housed within microwells has not received much attention to date. Herein, we study the coalescence of droplets in a two-phase system in a microwell driven by surface acoustic waves (SAWs). The microwell structure, together with symmetric exposure to SAW irradiation, coupled from beneath the microwell via a piezoelectric substrate, gives rise to the formation of a pair of counter-rotating vortices that enable droplet transport, trapping, and coalescence. We elucidate the physics of the coalescence phenomenon using a scaling analysis of the relevant forces, namely, the acoustic streaming-induced drag force, the capillary and viscous forces associated with the drainage of the thin continuous phase film between the droplets and the van der Waals attraction force. We confirm that droplet-droplet interface contact is established through the formation of a liquid bridge, whose neck radius grows linearly in time in the preceding viscous regime and proportionally with the square root of time in the subsequent inertial regime. Further, we investigate the influence of the input SAW power and droplet size on the film drainage time and demarcate the coalescence and non-coalescence regimes to derive a criterion for the onset of coalescence. The distinct deformation patterns observed for a pair of contacting droplets in both the regimes are elucidated and the possibility for driving concurrent coalescence of multiple droplets is demonstrated. We expect the study will find relevance in the demulsification of immiscible phases and the mixing of samples/reagents within microwells for a variety of biochemical applications.

4.
J Acoust Soc Am ; 150(1): 307, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34340505

RESUMEN

The dynamical motion of a pair of microparticles exposed to acoustic standing waves and located at the pressure nodal plane is studied using numerical simulations and experiments. The insight into their dynamical behavior along the pressure nodal plane due to the competition between the axial primary radiation and interparticle forces is elucidated. An expression for axial primary radiation force acting on a particle is derived, and the particle dynamics is simulated using fluid-structure interaction model based on the arbitrary Lagrangian-Eulerian method. Considering the total radiation force acting on a particle is the sum of the axial primary radiation force and the interparticle force, three distinct dynamical regimes are observed depending upon the relative magnitudes of the acoustic forces which in turn depend on the gradient of the acoustic energy density. Acceleration, deceleration, and constant velocity motion of the pair of approaching particles are observed, which are explained by the interplay of the acoustic and non-acoustic forces. The dynamical motion of the pair of particles predicted using the model is in very good agreement with the experimental observations.

5.
Clin Radiol ; 74(1): 3-12, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30031589

RESUMEN

Vascular disease, whether it be atherosclerosis, inflammatory, or hereditary vasculitide, is a systemic disorder with disease in one territory predictive of disease in another. Despite this, current approaches focus on single-territory assessment ignoring the global burden of disease. Advances in MRI have enabled us to surmount previous limitations and expand our approach to such conditions with the ability to simultaneously assess the entirety of the arterial tree in a single examination, allowing a staging examination as it were, of the vascular health in its totality. This review will cover the acquisition technique, reporting, clinical utility, and current evidence base for such an approach.


Asunto(s)
Angiografía por Resonancia Magnética , Imagen de Cuerpo Entero , Vasos Sanguíneos/diagnóstico por imagen , Humanos , Angiografía por Resonancia Magnética/métodos , Enfermedades Vasculares/diagnóstico por imagen , Imagen de Cuerpo Entero/métodos
6.
BMC Psychiatry ; 19(1): 225, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31337373

RESUMEN

BACKGROUND: Cognitive Bias Modification (CBM) has been used successfully as a computer-based intervention in disorders such as anxiety. However, CBM to modify interpretations of ambiguous information relevant to paranoia has not yet been tested. We conducted a qualitative investigation of a novel intervention called CBM for paranoia (CBM-pa) to examine its acceptability in patients with psychosis. METHODS: Eight participants with psychosis who completed CBM-pa were identified by purposive sampling and invited for a semi-structured interview to explore the facilitators and barriers to participation, optimum form of delivery, perceived usefulness of CBM-pa and their opinions on applying CBM-pa as a computerised intervention. The interviews were transcribed and analysed using thematic analysis by researchers working in collaboration with service users. RESULTS: Themes emerged relating to participants' perception about delivery, engagement, programme understanding, factors influencing experience, perceived impact and application of CBM-pa. CBM-pa was regarded as easy, straightforward and enjoyable. It was well-accepted among those we interviewed, who understood the procedure as a psychological intervention. Patients reported that it increased their capacity for adopting alternative interpretations of emotionally ambiguous scenarios. Although participants all agreed on the test-like nature of the current CBM-pa format, they considered that taking part in sessions had improved their overall wellbeing. Most of them valued the computer-based interface of CBM-pa but favoured the idea of combining CBM-pa with some form of human interaction. CONCLUSIONS: CBM-pa is an acceptable intervention that was well-received by our sample of patients with paranoia. The current findings reflect positively on the acceptability and experience of CBM-pa in the target population. Patient opinion supports further development and testing of CBM-pa as a possible adjunct treatment for paranoia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN: 90749868 . Retrospectively registered on 12 May 2016.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Trastornos Paranoides/terapia , Aceptación de la Atención de Salud/psicología , Trastornos Psicóticos/terapia , Adulto , Femenino , Humanos , Masculino , Trastornos Paranoides/psicología , Trastornos Psicóticos/psicología , Investigación Cualitativa , Interfaz Usuario-Computador
7.
J Pharm Sci ; 113(3): 772-784, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38043682

RESUMEN

The main objective of the experiment is to develop and evaluate hydrogel-bearing nanostructured lipid carriers (NLCs) loaded with ketoconazole (KTZ) for the effective treatment of candidiasis. The eugenol was used as a liquid lipid (excipient) for the development of KTZ-loaded NLCs and was explored for anti-fungal effect. The production of NLCs involves high energy processes to generate spherical, uniform particles, having a higher percentage of entrapment efficiency (%EE) for KTZ with 89.83 ± 2.31 %. The data from differential scanning calorimeter (DSC), powder x-ray diffraction (PXRD), and attenuated total reflectance (ATR) demonstrated the KTZ dispersion in NLCs. The NLCs loaded hydrogel possessed optimum spreadability and exhibited shear thinning behavior, indicating the ease of application of the final formulation. The 6.41-fold higher transdermal flux (Jss) was governed for KTZ from KTZ-NLC than coarse-KTZ, which explains the usefulness of NLCs. The KTZ-NLCs exhibited significant 2.58 and 6.35-fold higher retention in the stratum corneum and viable epidermis of the skin. The cell cytotoxicity studies using human dermal fibroblast cell (HDFS) lines depicted the usefulness of NLCs in reducing cell toxicities for KTZ. The KTZ-NLCs were found to inhibit planktonic growth and hyphal transition and showed a larger zone of inhibition against C. albicans strains with a MIC-50 value of 0.39 µg/mL. The antibiofilm activity of KTZ-NLCs at lower concentrations, in contrast to plain KTZ, explained the interaction of developed NLCs with fungal membranes. The overall results depicted the effectiveness of the loading KTZ in the lipid matrix to achieve antifungal activity against C. albicans.


Asunto(s)
Candida albicans , Nanoestructuras , Humanos , Eugenol/farmacología , Portadores de Fármacos/farmacología , Hidrogeles/farmacología , Lípidos/farmacología , Tamaño de la Partícula
8.
J Neurovirol ; 19(1): 82-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23329164

RESUMEN

Despite major advances in the development of antiretroviral therapies, currently available treatments have no effect on the production of HIV-Tat protein once the proviral DNA is formed. Tat is a highly neurotoxic and neuroinflammatory protein, but its effects may be modulated by antibody responses against it. We developed an indirect enzyme-linked immunosorbent assay and measured anti-Tat antibody titers in CSF of a well characterized cohort of 52 HIV-infected and 13 control individuals. We successfully measured anti-Tat antibodies in CSF of HIV-infected individuals with excellent sensitivity and specificity, spanning a broad range of detection from 10,000 to over 100,000 relative light units. We analyzed them for relationship to cognitive function, CD4 cell counts, and HIV viral load. Anti-Tat antibody levels were higher in those without neurocognitive dysfunction than in those with HIV-associated neurocognitive dysfunction (HAND) and in individuals with lower CD4 cell counts and higher viral loads. We provide details of an assay which may have diagnostic, prognostic, or therapeutic implications for patients with HAND. Active viral replication may be needed to drive the immune response against Tat protein, but this robust immune response against the protein may be neuroprotective.


Asunto(s)
Complejo SIDA Demencia/líquido cefalorraquídeo , Ensayo de Inmunoadsorción Enzimática/métodos , Anticuerpos Anti-VIH/líquido cefalorraquídeo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/inmunología , Complejo SIDA Demencia/inmunología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
9.
Reprod Domest Anim ; 48(3): 358-67, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23679988

RESUMEN

Immune privileged mesenchymal stem cells (MSCs) can differentiate into multiple cell types and possess great potential for human and veterinary regenerative therapies. This study was designed with an objective to isolate, expand and characterize buffalo bone marrow-derived MSCs (BM-MSCs) at molecular and cellular level. Buffalo BM-MSCs were isolated by Ficoll density gradient method and cultured in Dulbecco's modified Eagle's medium supplemented with fetal bovine serum (FBS). These cells were characterized through alkaline phosphatase (AP) staining, colony-forming unit (CFU) assay, mRNA expression analysis (CD 73, CD 90, CD 105, Oct4 and Nanog), immunolocalization along with flow cytometry (Stro 1, CD 73, CD 105, Oct4, Sox2 and Nanog) and in situ hybridization (Oct4 and Sox2). Multilineage differentiation (osteogenic, adipogenic and chondrogenic) was induced in vitro, which was further assessed by specific staining. Buffalo BM-MSCs have the capacity to form plastic adherent clusters of fibroblast-like cells and were successfully maintained up to 16(th) passage. These cells were AP positive, and further CFU assay confirmed their clonogenic property. RT-PCR analysis and protein localization study showed that buffalo BM-MSCs are positive for various cell surface markers and pluripotency markers. Cytoplasmic distribution of mRNA for pluripotency markers in buffalo BM-MSCs and multilineage differentiation were induced in vitro, which was further assessed by specific staining. To the best of our knowledge, this is the first report of buffalo BM-MSCs, which suggests that MSCs can be derived and expanded from buffalo bone marrow and can be used after characterization as a novel agent for regenerative therapy.


Asunto(s)
Células de la Médula Ósea/fisiología , Búfalos/fisiología , Células Madre Mesenquimatosas/fisiología , Adipogénesis/fisiología , Fosfatasa Alcalina , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Citometría de Flujo , Cariotipificación , Osteogénesis/fisiología
10.
Nat Genet ; 13(4): 472-6, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8696345

RESUMEN

The aetiology of multiple sclerosis (MS) is uncertain. There is strong circumstantial evidence to indicate it is an autoimmune complex trait. Risks for first degree relatives are increased some 20 fold over the general population. Twin studies have shown monozygotic concordance rates of 25-30% compared to 4% for dizygotic twins and siblings. Studies of adoptees and half sibs show that familial risk is determined by genes, but environmental factors strongly influence observed geographic differences. Studies of candidate genes have been largely unrewarding. We report a genome search using 257 microsatellite markers with average spacing of 15.2 cM in 100 sibling pairs (Table 1, data set 1 - DS1). A locus of lambda>3 was excluded from 88% of the genome. Five loci with maximum lod scores (MLS) of >1 were identified on chromosomes 2, 3, 5, 11 and X. Two additional data sets containing 44 (Table 1, DS2) and 78 sib pairs (Table 1, DS3) respectively, were used to further evaluate the HLA region on 6p21 and a locus on chromosome 5 with an MLS of 4.24. Markers within 6p21 gave MLS of 0.65 (non-significant, NS). However, D6S461, just outside the HLA region, showed significant evidence for linkage disequilibrium by the transmission disequilibrium test (TDT), in all three data sets (for DS1 chi2 = 10.8, adjusted P < 0.01)(DS2 and DS3 chi2 = 10.9, P < 0.0005), suggesting a modest susceptibility locus in this region. On chromosome 5p results from all three data sets (222 sib pairs) yielded a multipoint MLS of 1.6. The results support genetic epidemiological evidence that several genes interact epistatically to determine heritable susceptibility.


Asunto(s)
Esclerosis Múltiple/genética , Mapeo Cromosómico , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 2 , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 5 , Cromosomas Humanos Par 6 , Femenino , Humanos , Desequilibrio de Ligamiento , Complejo Mayor de Histocompatibilidad , Masculino , Linaje , Cromosoma X
11.
J Food Sci Technol ; 50(1): 197-202, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24425909

RESUMEN

Fresh ginger (Zingiber officinale Rosc.) suffers from weight loss, shrinkage, sprouting and rotting during storage after 3-4 weeks. This spoilage may be overcome by processing fresh produce to some value added products. An attempt was made to optimize the protocol for production of instant ginger candy. The experimental parameters considered were slice thickness (5.0-25.0 mm) and blanching duration (10-30 min) followed by dipping in 40°B and 75°B sugar solutions containing 2.0% citric acid respectively, for 1 and 2 h at 95 °C and dried at 60 °C for 1 h. RSM design was considered for this experiment and final products were evaluated for their textural properties, TSS, acidity, TSS: acid ratio, taste score and overall acceptability. The optimum product qualities in terms of hardness (2.08 kg), TSS (73.4%), acidity (1.31%), TSS: acid ratio (56.3), taste score (7.98) and overall acceptability (8.07) were obtained for slice thickness of 10.9 mm and blanching time of 24.9 min.

12.
SAR QSAR Environ Res ; : 1-20, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37941423

RESUMEN

The fast-increasing number of commercially produced chemicals challenges the experimental ecotoxicity assessment methods, which are costly, time-consuming, and dependent on the sacrifice of animals. In this regard, Quantitative Structure-Property/Activity Relationships (QSPR/QSAR) have led the way in developing ecotoxicity assessment models. In this study, QSAR models have been developed using the pEC50 values of 82 diverse agrochemicals or agro-molecules against a planktonic crustacean Daphnia magna with easily interpretable 2D descriptors. Moreover, a link among octanol-water partition coefficient (KOW), bio-concentration factor (BCF), and critical body residue (CBR) has been addressed, and their imputation for the prediction of the toxicity endpoint (EC50) has been done with an objective of the advanced exploration of several ecotoxicological parameters for toxic chemicals. The developed partial least squares (PLS) models were validated rigorously and proved to be robust, sound, and immensely well-predictive. The final Daphnia toxicity model derived from experimental derived properties along with computed descriptors emerged better in statistical quality and predictivity than those obtained solely from computed descriptors. Additionally, the pEC50 and other important properties (log KOW, log BCF, and log CBR) for a set of external agro-molecules, not employed in model development, were predicted to show the predictive ability of the models.

13.
Artículo en Inglés | MEDLINE | ID: mdl-37399973

RESUMEN

OBJECTIVE: To evaluate by in- vivo lymphoscintigraphy and SPECT-CT imaging, the lymphatic drainage patterns of para-nasal sinus(PNS) tumors. To confirm or refute the belief of the retropharyngeal lymph node (RPLN) being the significant draining lymph node for such tumors. METHODS: Prospective cohort study conducted on previously untreated PNS tumors with no clinico-radiological evidence of lymph node metastasis. Lymphoscintigraphy undertaken by nasal endoscopic assisted peritumoral injection of 99mTc Sulfur colloid. Injections were classified as anterior or posterior as per a vertical line along the maxillary sinus ostium. RESULTS: 17 patients were included. Lymphoscintigraphy successfully identified 17 sentinel nodes in 15 patients and was unsuccessful (lymphoscintigraphy failure) in 2 patients. Predominant sites of sentinel lymphatic drainage were noted to be the RPLN (n = 8; 47%), and Level I (n = 7; 42%). Occasional drainage was identified at the peri-parotid node(n = 1) and at Level II (n = 1). Contralateral drainage was noted in 2 patients (level I-1 and RPLN-1). Anterior injections drained predominantly to Level I (6/8) and RPLN (2/8), while posterior injections drained predominantly to the RPLN ( 6/7). The relative risk of RPLN being identified as the sentinel node was significantly higher for posteriorly placed injections than for anteriorly placed injections (RR- 3.43; 95% CI-1.0-11.8, p = 0.05). CONCLUSION: The RPLN is noted as a frequent draining node for sino-nasal tumours and merits routine attention in all sino-nasal tumors. The radio-colloid SPECT-CT technique described here offers an excellent in-vivo technique to further explore and validate the lymphatic drainage pathways of these tumours.


Asunto(s)
Linfocintigrafia , Biopsia del Ganglio Linfático Centinela , Humanos , Linfocintigrafia/métodos , Biopsia del Ganglio Linfático Centinela/métodos , Estudios Prospectivos , Radiofármacos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Coloides
14.
Reprod Domest Anim ; 47(6): 975-83, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22463675

RESUMEN

Cells are blessed with a group of stress protector molecules known as heat shock proteins (HSPs), amongst them HSP70, encoded by HSPA-1A gene, is most abundant and highly conserved protein. Variety of stresses hampers the developmental competence of embryos under in vivo and in vitro conditions. Present work was designed to study the quantitative expression of HSPA-1A mRNA in immature oocytes (IMO), matured oocytes (MO), in vitro produced (IVP) and in vivo-derived (IVD) buffalo embryos to assess the level of stress to which embryos are exposed under in vivo and in vitro culture conditions. Further, HSPA-1A gene sequence was analysed to determine its homology with other mammalian sequences. The mRNA expression analysis was carried out on 72 oocytes (40 IMO; 32 MO), 76 IVP and 55 IVD buffalo embryos. Expression of HSPA-1A was found in oocytes and throughout the developmental stages of embryos examined irrespective of the embryo source; however, higher (p < 0.05) expression was observed in 8-16 cell, morula and blastocyst stages of IVP embryos as compared to IVD embryos. Phylogenetic analysis of bubaline HSPA-1A revealed that it shares 91-98% identity with other mammalian sequences. It can be concluded that higher level of HSPA-1A mRNA in IVP embryos in comparison with in vivo-derived embryos is an indicator of cellular stress in IVP system. This study suggests need for further optimization of in vitro culture system in which HSPA-1A gene could be used as a stress biomarker during pre-implantation development.


Asunto(s)
Búfalos/embriología , Técnicas de Cultivo de Embriones/veterinaria , Fertilización In Vitro/veterinaria , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas HSP70 de Choque Térmico/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Femenino , Proteínas HSP70 de Choque Térmico/genética , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Conformación Proteica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Estrés Fisiológico
15.
J Food Sci Technol ; 49(4): 427-38, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23904651

RESUMEN

Ready-to-eat (RTE) potato-soy snacks were developed using high temperature short time (HTST) air puffing process and the process was found to be very useful for production of highly porous and light texture snack. The process parameters considered viz. puffing temperature (185-255 °C) and puffing time (20-60 s) with constant initial moisture content of 36.74% and air velocity of 3.99 m.s(-1) for potato-soy blend with varying soy flour content from 5% to 25% were investigated using response surface methodology following central composite rotatable design (CCRD). The optimum product in terms of minimum moisture content (11.03% db), maximum expansion ratio (3.71), minimum hardness (2,749.4 g), minimum ascorbic acid loss (9.24% db) and maximum overall acceptability (7.35) were obtained with 10.0% soy flour blend in potato flour at the process conditions of puffing temperature (231.0 °C) and puffing time (25.0 s).

16.
J Food Sci Technol ; 49(5): 556-63, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24082266

RESUMEN

An experiment was conducted on pear fruit (cv. 'Lagoon') to extend the shelf life by using different packaging materials. Fruits were packed in low density polyethylene (LDPE, 0.025 mm), polypropylene (PP, 0.025 mm), linear low density polyethylene (LLDPE, 0.0125 mm) and high density polyethylene (HDPE, 0.025 mm) with or without perforation and stored at ambient condition (25 ± 2 °C and 65.0 ± 5% RH). Periodical observations were recorded on CO2 & O2 concentration (%), physiological loss in weight (PLW, %), decay loss (%), firmness (kgf), colour value (colour difference and colour index), total soluble solid (TSS, °Brix), acidity (mg of malic acid/g), and ascorbic acid loss (%) at 3 days interval. Reduced rate of PLW and decay losses was recorded in pear fruits packed in PP non-perforated (8.04%) and PP perforated (12.5%), respectively as compared to other treatments. The maximum firmness (5.18 kgf) and minimum ascorbic acid loss (49.97%) were also recorded in PP non-perforated up to 12 and 15 days of storage, respectively. It could be inferred that the, PP non-perforated (0.025 mm) was the most suitable packaging materials for extending the shelf life of pear fruits up to 15 days at ambient condition.

17.
Phys Rev E ; 105(3-2): 035103, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35428152

RESUMEN

We study particle trapping driven by the axial primary radiation force (A-PRF) in shaped traps exposed to standing bulk acoustic waves (S-BAW) using numerical simulations and experiments. The utilization of the stronger A-PRF as the main retention force is a consequence of standing-wave formation along the flow direction, instead of the orthogonal direction as in the case of traditionally used lateral-PRF S-BAW trapping setups. The study of particle dynamics reveals that the competition between A-PRF and viscous drag force governs particle trajectory. The ratio of the acoustic energy to the viscous work (ß) provides a general criterion for particle trapping at a distinctive off-node site that is spatially controllable. Particles get trapped for ß≥ß_{cr} at some distance away from the nodal plane and the distance varies as ß^{-c} (c=0.6-1.0). The use of A-PRF as the retention force could potentially allow traditional S-BAW trapping systems to envisage high-throughput advancements surpassing the current standards in cell-handling unit operations.

18.
Nat Med ; 6(12): 1380-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11100124

RESUMEN

Neurological disorders develop in most people infected with human immunodeficiency virus type 1 (HIV-1). However, the underlying mechanisms remain largely unknown. Here we report that binding of HIV-1 transactivator (Tat) protein to low-density lipoprotein receptor-related protein (LRP) promoted efficient uptake of Tat into neurons. LRP-mediated uptake of Tat was followed by translocation to the neuronal nucleus. Furthermore, the binding of Tat to LRP resulted in substantial inhibition of neuronal binding, uptake and degradation of physiological ligands for LRP, including alpha2-macroglobulin, apolipoprotein E4, amyloid precursor protein and amyloid beta-protein. In a model of macaques infected with a chimeric strain of simian-human immunodeficiency virus, increased staining of amyloid precursor protein was associated with Tat expression in the brains of simian-human immunodeficiency virus-infected macaques with encephalitis. These results indicate that HIV-1 Tat may mediate HIV-1-induced neuropathology through a pathway involving disruption of the metabolic balance of LRP ligands and direct activation of neuronal genes.


Asunto(s)
Complejo SIDA Demencia/etiología , Productos del Gen tat/metabolismo , VIH-1 , Neuronas/metabolismo , Receptores Inmunológicos/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Apolipoproteína E4 , Apolipoproteínas E/metabolismo , Ganglios Basales/patología , Transporte Biológico , Encéfalo/citología , Encéfalo/patología , Células CHO , Cricetinae , Endocitosis , Feto , Edad Gestacional , Proteoglicanos de Heparán Sulfato/metabolismo , Humanos , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad , Macaca , Células PC12 , Ratas , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , alfa-Macroglobulinas/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana
19.
Nano Lett ; 10(4): 1383-6, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20196539

RESUMEN

An unexpected presence of ferromagnetic (FM) ordering in nanostructured nonmagnetic metal oxides has been reported previously. Though this property was attributed to the presence of defects, systematic experimental and theoretical studies to pinpoint its origin and mechanism are lacking. While it is widely believed that oxygen vacancies are responsible for FM ordering, surprisingly we find that annealing as-prepared samples at low temperature (high temperature) in flowing oxygen actually enhances (diminishes) the FM ordering. For these reasons, we have prepared, annealed in different environments, and measured the ensuing magnetization in micrometer and nanoscale ZnO with varying crystallinity. We further find from our magnetization measurements and ab initio calculations that a range of magnetic properties in ZnO can result, depending on the sample preparation and annealing conditions. For example, within the same ZnO sample we have observed ferro- to para- and diamagnetic responses depending on the annealing conditions. We also explored the effects of surface states on the magnetic behavior of nanoscale ZnO through detailed calculations.


Asunto(s)
Magnetismo , Nanoestructuras/química , Óxido de Zinc/química , Nanotecnología/métodos , Oxígeno/química , Tamaño de la Partícula , Teoría Cuántica , Propiedades de Superficie , Temperatura
20.
J Neurol Sci ; 423: 117358, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33653604

RESUMEN

Reactivation of Human Endogenous Retrovirus K (HERV-K), subtype HML-2, has been associated with pathophysiology of amyotrophic lateral sclerosis (ALS). We aimed to assess the efficacy of antiretroviral therapy in inhibiting HML-2 in patients with ALS and a possible association between the change in HML-2 levels and clinical outcomes. We studied the effect of 24-weeks antiretroviral combination therapy with abacavir, lamivudine, and dolutegravir on HML-2 levels in 29 ALS patients. HML-2 levels decreased progressively over 24 weeks (P = 0.001) and rebounded within a week of stopping medications (P = 0.02). The majority of participants (82%), defined as "responders", experienced a decrease in HML-2 at week 24 of treatment compared to the pre-treatment levels. Differences in the evolution of some of the clinical outcomes could be seen between responders and non-responders: FVC decreased 23.69% (SE = 11.34) in non-responders and 12.71% (SE = 8.28) in responders. NPI score decreased 91.95% (SE = 6.32) in non-responders and 53.05% (SE = 10.06) in responders (P = 0.01). Thus, participants with a virological response to treatment showed a trend for slower progression of the illness. These findings further support the possible involvement of HML-2 in the clinical course of the disease.


Asunto(s)
Esclerosis Amiotrófica Lateral , Retrovirus Endógenos , Infecciones por VIH , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/genética , Infecciones por VIH/tratamiento farmacológico , Humanos
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