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Why have technology standards for teachers? I visited a classroom not long ago to set up for a professional development session. The teacher directed me to a computer and said [...]

Drug therapy for depression Goal: To provide the pharmacist with the practical knowledge to recommend rational drug therapy for depression when appropriate. Objectives: After completing this lesson, the pharmacists should [...]

Many irrigation scheduling methods utilized in commercial production settings rely on soil water sensors that are normally purchased as off-the-shelf technology or through contracted services that install and monitor readings throughout the season. These systems often assume a direct relationship between the parameters measured by these soil water sensors (voltage, unitless values, or calibrated soil moisture values) and the water use and deficit stress of the crop. Because of this assumed relationship, these sensors are purported to be useful for triggering irrigation applications by monitoring relative changes in sensor values that represent either a “dry” or “wet” condition in the field. However, there is often little confirmation that these sensors accurately reflect crop water uptake or what soil depths will best represent that relationship. In an attempt to quantify the association between the use of soil water sensors and crop water use in a commercial potato field, measurements of soil water using capacitance probes and plant water use using sap flow sensors were monitored. Measurements were taken in two water application treatments: a normal (full) and partial irrigation schedule because it was hypothesized that the relative strength of the relationship between sensor reading and crop water use may be highly dependent on field soil water status. Relative soil moisture readings and plant water use data were compiled and both linear and quadratic regressions were performed. The correlation between sap flow and soil sensor readings was significant; but the relationship was relatively weak with the strength dependent on the soil depth that was monitored, indicating that care must be taken when utilizing sensor readings for irrigation scheduling. Muchos métodos de programación de riego que se utilizan en instalaciones de producción comercial se respaldan en sensores de agua en el suelo que generalmente se compran como tecnología “fuera de la plataforma” o a través de servicios contratados que instalan y le dan seguimiento a las lecturas a lo largo del ciclo. Estos sistemas con frecuencia asumen una relación directa entre los parámetros medidos por estos sensores de agua en el suelo (voltaje, valores sin unidades, o valores calibrados de la humedad del suelo) y el uso del agua y el agobio por déficit del cultivo. Debido a esta asumida relación, estos sensores son formalmente útiles para disparar aplicaciones de riego mediante el monitoreo de los cambios relativos en los valores del sensor que representan ya sea una condición “seca” o “húmeda” en el campo. No obstante, a menudo hay poca confirmación de que estos sensores reflejan con precisión la absorción del agua por el cultivo o a que profundidades del suelo representarán mejor esa relación. En un intento para cuantificar la asociación entre el uso de los sensores del agua del suelo y el uso del agua por el cultivo en una siembra comercial de papa, se dio seguimiento a las mediciones del agua en el suelo utilizando sondas de capacitancia y el uso de agua por la planta con sensores de flujo de savia. Se tomaron las mediciones en dos tratamientos de aplicación de agua: una programación normal (completa) y otra parcial de riego, porque se tuvo la hipótesis de que la fuerza relativa de la relación entre la lectura del sensor y el uso de agua por el cultivo pudiera ser altamente dependiente de la situación del agua del suelo en el campo. Se recopilaron datos de las lecturas de la humedad relativa del suelo y del uso de agua por la planta y se les hicieron regresiones lineales y cuadráticas. La correlación entre el flujo de savia y las lecturas de los sensores del suelo fue significativa primero bajo condiciones de agua limitada en el suelo; pero la relación fue relativamente débil con la fuerza dependiente de la profundidad del suelo que se monitoreó, indicando que se debe tener cuidado cuando se utilicen lecturas de sensores para la programación del riego.

The article offers the author's insights on the impact of copying one's artwork. He states that it is acceptable when a person in skill development process tends to create more advanced work than copying others' works. He mentions the copyright law which recognizes the value of an original work, giving the creator the right to defend from being copied. He suggests that new artists must search for an idea or concept in which they could incorporate art and personality to develop original works.

Cytochemical studies on uninseminated mature eggs of Limulusdemonstrate the presence of carbohydrates, lipids and proteins in the egg envelopes and yolk. The vitelline envelope, cortical region and yolk are rich in 1,2-glycols, with the vitelline envelope containing fewer reactive 1,2-glycol groups than other components of the egg. Neutral mucopolysaccharides are found in the cortical region and yolk, but only the cortical region of the eggs demonstrate the presence of sulfated mucosubstances (which are in part glycoprotein in nature) and glucose-6-phosphatase. Protein is evident in all egg components. Biochemical analysis demonstrate the protein in the egg envelopes of uninseminated eggs is composed of sixteen amino acids while that of developing eggs contain seventeen amino acid residues. Electrovalent linkages and non-S-S-covalent linkages between protein chains are shown to be instrumental in maintaining the structural integrity of Limulusegg envelopes. Neutral lipids, unsaturated lipids, phospholipids and fatty acids are demonstrated in yolk bodies and lipoproteins, unsaturated lipids and fatty acids constitute part of the egg envelopes. DNA is concentrated in the cortical region and the yolk bodies.