An Assessment of Performance Measures in the Transportation Development Act

"This report examines the performance measures requirements in California’s Transportation Development Act (TDA) of 1971. The TDA is an important source of funding for the state’s public transit agencies, representing approximately 18 percent of their total (2018) revenue between the TDA’s two funds (LTF and STA). Since the TDA’s passage in 1971, the transit operating environment in California has changed, in some cases dramatically. The state has nearly doubled in population (20.4 million in 1971 to 39.8 million in 2019), traffic has worsened considerably, climate change is now a central public policy focus, and many places around the state are investing heavily in making public transit a viable alternative to driving. Our research examined the TDA’s performance requirements and their effects on the state’s transit operators. We also considered alternative approaches to both transit finance and performance requirements, by studying transit funding programs in 13 other states that invest significant amounts of funding in transit. In brief, we find that the TDA’s use of performance measurements to allocate funding is unusual. The states we studied do not for the most part make funding contingent on performance, thereby avoiding the unproductive and difficult-to-implement “death penalty” (Taylor, 1995) of withholding subsidies for a much-needed public service. In several of the cases analyzed, by contrast, states guarantee specific levels or amounts of funding for transit service.To examine how the TDA’s performance measures are working, we conducted a survey of California transit professionals at agencies and at Regional Transportation Planning Agencies (RTPAs). That California’s aspirations for transit have evolved over the years is reflected in the frequent loopholes and exemptions the legislature has added to the TDA to give struggling operators more latitude to receive funding in order to meet multiple goals and objectives while staying in compliance with a single cost-effectiveness goal. The extent and frequency with which these exemptions have occurred suggests that the larger aims for public transit, and indeed the goals for the TDA program itself, have evolved, and need to be re-thought holistically, rather than incrementally.Accordingly we offer six recommendations concerning transit performance assessment in the TDA.

An alternative evolutionary strategy to optimize photoreaction quantum yields

Photoisomerization of a protein bound chromophore is the basis of light sensing of many photoreceptors. We tracked Z-to-E photoisomerization of Cph1 phytochrome chromophore PCB in the Pr form in real-time. Two different phycocyanobilin (PCB) ground state geometries with different ring D orientations have been identified. The pre-twisted and hydrogen bonded PCBa geometry exhibits a time constant of 30 ps and a quantum yield of photoproduct formation of 29%, about six times slower and ten times higher than that for the non-hydrogen bonded PCBb geometry. This new mechanism of pre-twisting the chromophore by protein-cofactor interaction optimizes yields of slow photoreactions and provides a scaffold for photoreceptor engineering

Algunos datos para la monitorización del acuífero Alto Guadalentín

En el presente artículo se presentan un análisis de series temporales de datos relativos a la evolución niveles piezométricos de la zona del Alto del Guadalentín (Murcia) y un análisis paralelo de series temporales de datos GNSS referentes a las altitudes de la zona. El objetivo de este análisis pretende establecer posibles correlaciones entre la subsidencia recogida por la red de estaciones GPS nacionales y el aumento de la profundidad piezométrica a la que se encuentran los acuíferos. Este objetivo se desarrollará mediante el análisis de los niveles piezométricos en comparación con las diferencias de altitud registradas en estaciones GNSS nacionales

Soil Nematodes of Brassica rapa: Influence of Temperature and pH

An investigation of the soil nematodes associated with Brassica rapa and the effects of temperature and pH on their populations was carried out. The nematodes recovered were categorized into three ecologically functional groups; Nitrogen Releasing Nematodes (NRN, bacterial- and fungal- feeders), Plant-Parasitic Nematodes (PPN), and Pest Suppressor Nematodes (PSN, Carnivorous or predatory (Ca) and Omnivorous (Om), nematodes). While over 67% of the NRN were bacterial feeding nematodes (Ba2), dominated by Plectus and Acrobeloides; over 65% of the PPN were contributed by the Pl3 nematodes dominated by Helicotylenchus mucronatus and Rotylenchus buxophilus; and the PSN were dominated (over 63%) by the omnivores (Om4; Mesodorylaimus and Dorylaimus). Populations of all the nematode categories recovered fluctuated significantly (P < 0.01) during the sampling period. All the nematode groups were similarly weakly negatively correlated with pH and temperature. Approximately 1000 H. mucronatus nematodes/100 mL of soil was recorded. This is 10x the value for which the management of PPN is recommended. The entire soil nematode food web structure was represented in the nematodes recovered, all groups of nematodes responded similarly to environmental changes, all groups of nematodes tended to be acidophilic and thermophobic, and the PPN could potentially be a threat for profitable B. rapa production

The kinetics and mechanism of the organo-iridium catalysed racemisation of amines

The dimeric iodo-iridium complex [IrCp*I2 ]2 (Cp*=pentamethylcyclopentadiene) is an efficient catalyst for the racemisation of secondary and tertiary amines at ambient and higher temperatures with a low catalyst loading. The racemisation occurs with pseudo-first-order kinetics and the orresponding four rate constants were obtained by monitoring the time dependence of the concentrations of the (R) and (S) enantiomers starting with either pure (R) or (S) and show a first-order dependence on catalyst concentration. Low temperature 1H NMR data is consistent with the formation of a 1:1 complex with the amine coordinated to the iridium and with both iodide anions still bound to the metal-ion, but at the higher temperatures used for kinetic studies binding is weak and so no saturation zero-order kinetics are observed. A cross-over experiment with isotopically labelled amines demonstrates the intermediate formation of an imine which can dissociate from the iridium complex. Replacing the iodides in the catalyst by other ligands or having an amide substituent in Cp* results in a much less effective catalysts for the racemisation of amines. The rate constants for a deuterated amine yield a significant primary kinetic isotope effect kH/kD = 3.24 ndicating that hydride transfer is involved in the rate-limiting step

Monocytes regulate the mechanism of T-cell death by inducing Fas-mediated apoptosis during bacterial infection.

Monocytes and T-cells are critical to the host response to acute bacterial infection but monocytes are primarily viewed as amplifying the inflammatory signal. The mechanisms of cell death regulating T-cell numbers at sites of infection are incompletely characterized. T-cell death in cultures of peripheral blood mononuclear cells (PBMC) showed 'classic' features of apoptosis following exposure to pneumococci. Conversely, purified CD3(+) T-cells cultured with pneumococci demonstrated necrosis with membrane permeabilization. The death of purified CD3(+) T-cells was not inhibited by necrostatin, but required the bacterial toxin pneumolysin. Apoptosis of CD3(+) T-cells in PBMC cultures required 'classical' CD14(+) monocytes, which enhanced T-cell activation. CD3(+) T-cell death was enhanced in HIV-seropositive individuals. Monocyte-mediated CD3(+) T-cell apoptotic death was Fas-dependent both in vitro and in vivo. In the early stages of the T-cell dependent host response to pneumococci reduced Fas ligand mediated T-cell apoptosis was associated with decreased bacterial clearance in the lung and increased bacteremia. In summary monocytes converted pathogen-associated necrosis into Fas-dependent apoptosis and regulated levels of activated T-cells at sites of acute bacterial infection. These changes were associated with enhanced bacterial clearance in the lung and reduced levels of invasive pneumococcal disease

Identification of peroxiredoxin-1 as a novel biomarker of abdominal aortic aneurysm

Objective— In the search of novel biomarkers of abdominal aortic aneurysm (AAA) progression, proteins released by intraluminal thrombus (ILT) were analyzed by a differential proteomic approach. Methods and Results— Different layers (luminal/abluminal) of the ILT of AAA were incubated, and the proteins released were analyzed by 2-dimensional difference in-gel electrophoresis. Several differentially expressed proteins involved in main AAA pathological mechanisms (proteolysis, oxidative stress, and thrombosis) were identified by mass spectrometry. Among the proteins identified, peroxiredoxin-1 (PRX-1) was more released by the luminal layer compared with the abluminal layer of the ILT, which was further validated by Western blot, ELISA, and immunohistochemistry. We demonstrated increased PRX-1 serum levels in AAA patients compared with healthy subjects and also positive correlation among PRX-1 and AAA diameter, plasmin-antiplasmin, and myeloperoxidase levels. Finally, a prospective study revealed a positive correlation between PRX-1 serum levels and AAA expansion rate. Moreover, the combination of PRX-1 and AAA size had significantly additive value in predicting growth. Conclusion— Several proteins associated with AAA pathogenesis have been identified by a proteomic approach in ILT-conditioned medium. Among them, PRX-1 serum levels are increased in AAA patients and correlate with AAA size and growth rate, suggesting the potential use of PRX-1 as a biomarker for AAA evolution. </jats:sec

Propiedades mecánicas del concreto f’c = 210 kg/cm2 al adicionar aserrín y fibra de madera tornillo

Esta investigación tuvo como objetivo general determinar la influencia de la adición de aserrín y fibra de madera tornillo para mejorar las propiedades mecánicas del concreto f’c = 210 kg/cm2. El método de la investigación fue científico, su diseño de investigación fue experimental, su tipo de investigación fue de alcance aplicada, de enfoque cuantitativo, y el nivel de explicación fue explicativo. Se presenta la población por los ensayos mecánico y físico, slump, ensayo de compresión y ensayo de flexión, que se obtengan de las diversas mezclas al adicionar aserrín y fibra de madera tornillo para edificaciones, dándose en los 3 diseños restantes; por otra parte, las muestras estuvieron compuestas por 27 muestras de concreto simple con resistencia de f'c = 210 kg/cm2, a las que se les agregó aserrín de madera tornillo, y 9 muestras de concreto estándar, todas con dimensiones de 15 cm de diámetro. Se eligió el método de muestreo no probabilístico, porque no se basa en fórmulas estadísticas, sino en criterios de selección elaborados por el investigador, tomando en consideración las circunstancias concretas que se han observado en el transcurso del análisis