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3.
J Phys Chem A ; 119(24): 6309-16, 2015 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-25985076

RESUMEN

Analyses of the crystal field energy levels of the series LaCl3:Ln(3+) using a semiempirical Hamiltonian shows that only five ions (Pr, Nd, Pm, Dy, Ho) meet the criteria to avoid overfitting of the atomic part. A new parameter (SNES) has been introduced to represent the strength of the normalized electrostatic repulsion for these ions. This parameter varies linearly (R(2)adj = 0.9994, N = 5) with the reciprocal of the radius of the tripositive lanthanide ion, as expected from the form of repulsive Coulomb interaction. The Slater parameters from the crystal field analyses, F(k)(corr) (i.e., corrected for the effects of the two-particle component of the three-body operator associated with the T(2) parameter), exhibit an exponential variation with the number of electrons, n, in 4f(n). This is explained by reference to the radial part of a hydrogen-like wave function. The ratio of F(k)(corr) with the ab initio free ion Slater parameter F(k)(ab initio) varies linearly with n. Fitted parameters F(k)(corr: free ion) from the free ion data for Pr(3+) and Nd(3+) show that the corresponding ab initio values are between 14 and 27% too high. The spin-orbit coupling constant from crystal field analyses (ζ4f) exhibits a quartic variation with atomic number, and the ratio ζ4f/ζ4f(ab initio) follows an exponential growth model with n. The results serve to confirm the hypothesis that smooth trends can be observed across the Ln(3+) series for the fitted parameters despite the fact that the majority of experimental data is lacking.

4.
J Phys Chem Lett ; 15(9): 2319-2324, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38386623

RESUMEN

Cr3+ doped near-infrared phosphors hold significant applications and generate considerable research interest. The critical parameter for assessing the strength of the crystal field for Cr3+ in the Tanabe-Sugano diagram is the boundary value of Dq/B, representing the ratio of crystal field splitting to the Racah parameter B. Nevertheless, there are conflicting values for this parameter, as reported in various studies, such as 2.1, 2.2, and 2.3 for C/B = 4.5-4.8. Moreover, some Cr3+ doped phosphors with wide-band emissions exhibit a Dq/B value that falls within the region of a contradictory strong field. In this study, we numerically determine the boundary value of Dq/B, which distinguishes between strong and weak fields. The results then demonstrate a dependence on the host material and are correlated with the values of Racah parameters B and C. This work resolves the inconsistency between the boundary values of Dq/B and the emission profile of Cr3+, providing researchers with a more profound comprehension of Cr3+ luminescence.

5.
J Anim Sci ; 1012023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37335911

RESUMEN

Precision livestock farming (PLF) offers a strategic solution to enhance the management capacity of large animal groups, while simultaneously improving profitability, efficiency, and minimizing environmental impacts associated with livestock production systems. Additionally, PLF contributes to optimizing the ability to manage and monitor animal welfare while providing solutions to global grand challenges posed by the growing demand for animal products and ensuring global food security. By enabling a return to the "per animal" approach by harnessing technological advancements, PLF enables cost-effective, individualized care for animals through enhanced monitoring and control capabilities within complex farming systems. Meeting the nutritional requirements of a global population exponentially approaching ten billion people will likely require the density of animal proteins for decades to come. The development and application of digital technologies are critical to facilitate the responsible and sustainable intensification of livestock production over the next several decades to maximize the potential benefits of PLF. Real-time continuous monitoring of each animal is expected to enable more precise and accurate tracking and management of health and well-being. Importantly, the digitalization of agriculture is expected to provide collateral benefits of ensuring auditability in value chains while assuaging concerns associated with labor shortages. Despite notable advances in PLF technology adoption, a number of critical concerns currently limit the viability of these state-of-the-art technologies. The potential benefits of PLF for livestock management systems which are enabled by autonomous continuous monitoring and environmental control can be rapidly enhanced through an Internet of Things approach to monitoring and (where appropriate) closed-loop management. In this paper, we analyze the multilayered network of sensors, actuators, communication, networking, and analytics currently used in PLF, focusing on dairy farming as an illustrative example. We explore the current state-of-the-art, identify key shortcomings, and propose potential solutions to bridge the gap between technology and animal agriculture. Additionally, we examine the potential implications of advancements in communication, robotics, and artificial intelligence on the health, security, and welfare of animals.


Precision technologies are revolutionizing animal agriculture by enhancing the management of animal welfare and productivity. To fully realize the potential benefits of precision livestock farming (PLF), the development and application of digital technologies are needed to facilitate the responsible and sustainable intensification of livestock production over the next several decades. Importantly, the digitalization of agriculture is expected to provide collateral benefits of ensuring audibility in value chains while assuaging concerns associated with labor shortages. In this paper, we analyze the multilayered network of sensors, actuators, communication, and analytics currently in use in PLF. We analyze the various aspects of sensing, communication, networking, and intelligence on the farm leveraging dairy farms as an example system. We also discuss the potential implications of advancements in communication, robotics, and artificial intelligence on the security and welfare of animals.


Asunto(s)
Crianza de Animales Domésticos , Inteligencia Artificial , Animales , Agricultura , Granjas , Ganado , Tecnología
6.
J Nanosci Nanotechnol ; 12(3): 2417-23, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22755068

RESUMEN

Successful doping of Eu3+ ions into ZnO nanocrystals has been realized by using a low temperature wet chemical doping technique. The substitution of Eu3+ for Zn2+ is shown to be dominant in the Eu-doped ZnO nanocrystals by analyzing the X-ray diffraction patterns, transmission electron microscopy images, Raman and selectively excited photoluminescence spectra. Measurement of the luminescence from the samples shows that the excited ZnO transfers the excited energy efficiently to the doped Eu3+ ions, giving rise to efficient emission at red spectral region. The red emission quantum yield is measured to be 31% at room temperature. The temperature dependence of photoluminescence and the photoluminescence excitation spectra have also been investigated, showing strong energy coupling between the ZnO host and Eu3+ ions through free and bound excitons. The result indicates that Eu3+ ion-doped ZnO nanocrystals are promising light-conversion materials and have potential application in highly distinguishable emissive flat panel display and LED backlights.

7.
Animals (Basel) ; 11(12)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34944293

RESUMEN

Immediate and short-term changes in diet composition can support individualized, real-time interventions in precision dairy production systems, and might increase feed efficiency (FE) of dairy cattle in the short-term. The objective of this study was to determine immediate and short-term effects of changes in diet composition on production parameters of dairy cattle fed varying amounts of top dressed commodities. A 4 × 4 replicated Latin square design was used to evaluate responses of twenty-four Holstein cows fed either no top dress (Control) or increasing amounts of: corn grain (CG), soybean meal (SBM), or chopped mixed grass hay (GH) top dressed on a total mixed ration (TMR) over four, 9-day periods. Throughout each period, top dressed commodities were incrementally increased, providing 0% to 20% of calculated net energy of lactation (NEL) intake. Measured production responses were analyzed for each 9-d period using a mixed-effects model considering two different time ranges. Samples collected from d 3 and 4 and from d 7 and 8 of each period were averaged and used to reflect "immediate" vs. "short-term" responses, respectively. In the immediate response time frame, control fed cows had lower milk yield, milk fat yield, and milk true protein yield than CG and SBM supplemented animals but similar responses to GH supplemented animals. Milk fat and protein percentages were not affected by top dress type in the immediate term. In the short-term response time-frame, GH supplemented animals had lower DMI and milk fat yield than all other groups. Control and GH supplemented cows had lower milk yield than CG and SBM fed cows. In the immediate response time frame, FE of SBM supplemented cows was superior to other groups. In the short-term time frame, FE of GH and SBM groups was improved over the control group. Results suggest that lactating dairy cows show rapid performance responses to small (<20% NEL) changes in dietary composition, which may be leveraged within automated precision feeding systems to optimize efficiency of production. Before this potential can be realized, further research is needed to examine integration of such strategies into automatic feeding systems and downstream impacts on individual animal FE and farm profitability.

8.
J Comp Pathol ; 137 Suppl 1: S72-5, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17560592

RESUMEN

Vaccination of dams with modified-live canine distemper virus (CDV) vaccines will elicit high concentrations of colostral antibody, that although vital for protection of the pup during the first weeks of life, can interfere with active vaccination against the virus. In the present study, 12 pups, 7-9 weeks of age, with maternally derived immunity to CDV, were vaccinated with a canarypox-vectored CDV vaccine. These pups were protected against intravenous challenge with CDV. Three littermate pups that were unvaccinated all developed clinical signs of infection after challenge, and two of these control pups died.


Asunto(s)
Animales Recién Nacidos/inmunología , Anticuerpos Antivirales/inmunología , Virus del Moquillo Canino/inmunología , Inmunidad Materno-Adquirida/inmunología , Inmunización/veterinaria , Animales , Virus de la Viruela de los Canarios/inmunología , Moquillo/inmunología , Moquillo/prevención & control , Perros , Femenino , Inmunización/métodos , Vacunación/métodos , Vacunación/veterinaria , Vacunas Virales/uso terapéutico
9.
Ear Nose Throat J ; : 1455613221139408, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36377117
10.
Sci Rep ; 6: 28465, 2016 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-27334357

RESUMEN

Positively charged antimicrobial peptides have become promising agents for the treatment of cancer by inducing apoptosis though their preferential binding and disruption of negatively charged membranes, such as the mitochondrial membrane. (KLAKLAK)2 is such a peptide but due to its polarity, it cannot cross the cellular membrane and therefore relies on the use of a delivery agent. For targeted delivery, previous studies have relied on cell penetrating peptides, nanoparticles or specific biomarkers. Herein, we investigated the first use of pHLIP to selectively target and directly translocate (KLAKLAK)2 into the cytoplasm of breast cancer cells, based on the acidic tumor micro-environment. With the goal of identifying a lead conjugate with optimized selective cytotoxicity towards cancer cells, we analyzed a family of (KLAKLAK)2 analogs with varying size, polarity and charge. We present a highly efficacious pHLIP conjugate that selectively induces concentration- and pH-dependent toxicity in breast cancer cells.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Proteínas de la Membrana/química , Secuencia de Aminoácidos , Péptidos Catiónicos Antimicrobianos/síntesis química , Péptidos Catiónicos Antimicrobianos/toxicidad , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Humanos , Concentración de Iones de Hidrógeno , Proteínas de la Membrana/síntesis química , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Técnicas de Síntesis en Fase Sólida
11.
J Nanosci Nanotechnol ; 5(9): 1455-64, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16193958

RESUMEN

This paper reviews the syntheses, particle-size measurements and various aspects of the optical spectra of lanthanide ion doped insulating nanomaterials, with the focus upon the sesquioxides, and it contrasts their behaviour with bulk materials.


Asunto(s)
Cristalización/métodos , Electroquímica/métodos , Elementos de la Serie de los Lantanoides/química , Luminiscencia , Nanoestructuras/química , Nanoestructuras/ultraestructura , Conductividad Eléctrica , Instalación Eléctrica , Electroquímica/instrumentación , Campos Electromagnéticos , Iones , Elementos de la Serie de los Lantanoides/análisis , Luz , Ensayo de Materiales , Conformación Molecular , Nanoestructuras/análisis , Tamaño de la Partícula , Propiedades de Superficie
13.
Atherosclerosis ; 38(3-4): 321-6, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7225171

RESUMEN

The effects of repeated bleeding (15 ml/day/kg b.wt. on 3 consecutive days) on plasma lipids, especially on high density lipoprotein (HDL)-cholesterol were studied in rabbits. As a result of the bleeding, plasma triglycerides (TG) increased from a mean of 0.61 (SD range 0.34-1.09) mmol/l to 2.86 (1.16-7.12) mmol/l (P less than 0.02). Plasma total cholesterol (TC) increased from 1.4 +/- 0.5 (SD) mmol/l to 2.0 +/- 0.5 mmol/l. The concentration of HDL-cholesterol, however, decreased from 0.72 +/- 0.16 mmol/l to 0.48 +/- 0.23 mmol/l (P less than 0.02). The HDL-cholesterol/TC ratio decreased from 0.57 +/- 0.17 to 0.29 +/- 0.15 (P less than 0.05). In connection with the haemorrhagic hyperlipidaemia a negative correlation (P less than 0.01) appeared between plasma TG and HDL-cholesterol. It is concluded that hypoxia, being the primary cause of haemorrhagic hyperlipidaemia, may be one factor regulating HDL-cholesterol concentrations and thereby possibly the development of atherosclerosis.


Asunto(s)
Colesterol/sangre , Hemorragia/complicaciones , Hiperlipidemias/complicaciones , Lipoproteínas HDL/sangre , Animales , Conejos , Triglicéridos/sangre
14.
Atherosclerosis ; 38(3-4): 395-9, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7225178

RESUMEN

The effect of immune complexes on plasma lipids, especially on high density lipoprotein (HDL) cholesterol, was studied in rabbits. In rabbits immunized twice with bovine serum albumin (BSA) with an interval of about 6 weeks, a significant decrease in plasma HDL-cholesterol (P less than 0.01) and in the HDL/total cholesterol ratio (P less than 0.02) was found 6 days after the second BSA injection. As a result of repeated bleedings commenced 6 days after the second BSA injection, the changes in plasma triglycerides (TG) and total cholesterol (TC) were similar to those found previously in non-immunized rabbits. In contrast to the findings in non-immunized rabbits, no significant decrease in HDL-cholesterol was found as a consequence of the bleedings, but a negative correlation (P less than 0.05) between plasma TG and HDL-cholesterol appeared. It is concluded that immune complexes may affect plasma HDL-cholesterol concentrations and thereby possibly also the development of atherosclerosis.


Asunto(s)
Complejo Antígeno-Anticuerpo , Colesterol/sangre , Lipoproteínas HDL/sangre , Animales , Bovinos , Lípidos/sangre , Conejos , Albúmina Sérica Bovina/inmunología , Triglicéridos/sangre
15.
J Histochem Cytochem ; 29(7): 864-5, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6167612

RESUMEN

A monoclonal mouse antibody to human chorionic gonadotropin (hCG) was used in a modified unlabeled antibody enzyme-bridge staining method to demonstrate the localization of hCG in normal human placenta, pituitary gland, and six pituitary chromophobe adenomas. Mouse ascitic fluid containing monoclonal antibody could be diluted up to 1:500,000 for detection of hCG in the syncytiotrophoblast, whereas no staining was observed in the pituitary or adenomas even with high antibody concentrations (dilutions from 1:500 upward). Nonspecific background staining was negligible. These results demonstrate that monoclonal antibodies are suitable for immunohistochemical localization of antigens in tissues.


Asunto(s)
Adenoma/patología , Anticuerpos , Gonadotropina Coriónica/análisis , Hipófisis/citología , Neoplasias Hipofisarias/patología , Placenta/citología , Anticuerpos Monoclonales , Células Clonales , Femenino , Humanos , Técnicas para Inmunoenzimas , Embarazo , Coloración y Etiquetado
16.
J Clin Pathol ; 38(7): 818-24, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4019803

RESUMEN

The concentration of ferritin was measured in the pleural fluid of 108 patients with pleural effusions. In all groups of patients the ferritin concentration was higher in pleural fluid than in serum. The greatest differences, with up to 100 times more ferritin in the pleural fluid, were found for patients with rheumatoid pleurisy, malignant effusions, and empyema. In patients with non-malignant inflammatory pleural effusions the concentration of ferritin in pleural fluid correlated significantly with other pleural fluid indices of inflammation: there was a positive correlation with lactate dehydrogenase activity and a negative correlation with concentrations of glucose and complement components C3 and C4. Ferritin was detected immunocytochemically only in the macrophages found among the pleural fluid cells. Our study shows that large amounts of ferritin accumulate locally in the pleural cavity in certain types of pleural inflammation. The accumulation is probably partly the result of increased local reticuloendothelial system activity. Determination of the concentration of ferritin in pleural fluid may provide corroborative information for differential diagnosis and may further our understanding of the pathogenetic events that lead to the perpetuation of inflammatory activity in pleural effusions.


Asunto(s)
Ferritinas/metabolismo , Derrame Pleural/metabolismo , Adolescente , Adulto , Anciano , Artritis Reumatoide/metabolismo , Empiema/metabolismo , Femenino , Ferritinas/sangre , Insuficiencia Cardíaca/metabolismo , Humanos , L-Lactato Deshidrogenasa/metabolismo , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Masculino , Persona de Mediana Edad , Pleuresia/metabolismo
17.
Science ; 250(4980): 493, 1990 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-17751467
18.
J Dent Res ; 64(10): 1214-7, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3861652

RESUMEN

Teratogenic and toxicological effects of lidocaine administered during pregnancy were evaluated in the Sprague Dawley rat. High doses of lidocaine administered during specific periods of gestation were shown to produce no apparent adverse toxicological or teratogenic effects. Histological, enzymological, and physical features of the fetuses, utilizing conventional toxicological parameters, were all found to be normal following maternal administration of lidocaine. Analysis of these data suggests that the administration of lidocaine during pregnancy had no detectable adverse effects on the fetus.


Asunto(s)
Lidocaína/toxicidad , Preñez/efectos de los fármacos , Animales , Femenino , Feto/efectos de los fármacos , Edad Gestacional , Lidocaína/administración & dosificación , Hígado/efectos de los fármacos , Hígado/embriología , Intercambio Materno-Fetal , Embarazo , Ratas , Teratógenos
19.
Acta Neurochir Suppl ; 89: 119-23, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15335111

RESUMEN

Treatment of patients suffering from severe head injury is so far restricted to general procedures, whereas specific pharmacological agents of neuroprotection including hypothermia have not been found to improve the outcome in clinical trials. Albeit effective, symptomatic measures of the preclinical rescue of patients (i.e. stabilization or reestablishment of the circulatory and respiratory system) or of the early clinical care (e.g. prompt diagnosis and treatment of an intracranial space occupying mass, maintenance of a competent circulatory and respiratory system, and others) by and large constitute the current treatment based on considerable organizational and logistical efforts. These and other components of the head injury treatment are certainly worthwhile of a systematic analysis as to their efficacy or remaining deficiencies, respectively. Deficits could be associated with delays of providing preclinical rescue procedures (e.g. until intubation of the patient or administration of fluid). Delays could also be associated in the hospital with the diagnostic establishment of intracranial lesions requiring prompt neurosurgical intervention. By support of the Federal Ministry of Education and Research and under the auspices of the Forschungsverbund Neurotraumatology, University of Munich, a prospective system analysis was carried out on major aspects of the pre- and early clinical management at a population based level in patients with traumatic brain injury. Documentation of pertinent data was made from August 1998 to July 1999 covering a catchment area of Southern Bavaria (5.6 mio inhabitants). Altogether 528 cases identified to suffer from severe head injury (GCS < or = 8 or deteriorating to that level within 48 hrs) were enrolled following admission to the hospital and establishment of the diagnosis. Further, patients dying on the scene or during transport to the hospital were also documented, particularly as to the frequency of severe head injury as underlying cause of mortality. The analysis included also cases with additional peripheral trauma (polytrauma). The efficacy of the logistics and organization of the management was studied by documentation of prognosis-relevant time intervals, as for example until arrival of the rescue squad at the scene of an accident, until intubation and administration of fluid, or upon hospital admission until establishment of the CT-diagnosis and commencement of surgery or transfer to the intensive care unit, respectively. The severity of cases studied in the present analysis is evident from a mortality of far above 40% of cases admitted to the hospital, which was increased by about 20% when including prehospital mortality. The outcome data notwithstanding, the emerging results demonstrate a high efficacy of the pre- and early clinical management, as indicated by a prompt arrival of the rescue squad at the scene, a competent prehospital and early clinical management and care, indicative of a low rate of avoidable complications. It is tentatively concluded on the basis of these findings that the patient prognosis is increasingly determined by the manifestations of primary brain damage vs. the development of secondary complications.


Asunto(s)
Traumatismos Craneocerebrales/mortalidad , Traumatismos Craneocerebrales/terapia , Servicios Médicos de Urgencia/estadística & datos numéricos , Sistemas de Registros Médicos Computarizados/estadística & datos numéricos , Manejo de Atención al Paciente/métodos , Manejo de Atención al Paciente/estadística & datos numéricos , Documentación , Alemania/epidemiología , Humanos , Estudios Prospectivos , Índice de Severidad de la Enfermedad
20.
Artículo en Inglés | MEDLINE | ID: mdl-2244186

RESUMEN

The increasing availability and use of immunoassays in clinical chemistry have revealed a number of endogenous interferences. Solid-phase sandwich immunoassays based on monoclonal antibodies are particularly sensitive to any factor able to bridge immunoglobulins together. Heterophilic immunoglobulin antibodies have been demonstrated in up to 40% of patient samples and to cause spuriously elevated results unless certain precautions are taken. Rheumatoid factors belong to the same category, but their affinity is usually too low to cause significant interference. Immunoscintigraphy generates high-titre anti-immunoglobulin responses causing serious interferences in immunoassays. Recently interfering factors of unknown nature causing nonspecific binding of enzyme-labelled antibodies have been observed. Spuriously decreased values can be caused by complement, which may interfere with antigen-binding to solid phase antibody. The aforementioned and other endogenous interferences in immunoassays are reviewed and methods for their elimination discussed.


Asunto(s)
Química Clínica/normas , Inmunoensayo/normas , Anticuerpos/inmunología , Antígenos/inmunología , Química Clínica/métodos , Proteínas del Sistema Complemento/inmunología , Ácidos Grasos no Esterificados/sangre , Humanos , Hiperlipidemias/sangre , Inmunoensayo/métodos , Reproducibilidad de los Resultados
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