Why participation matters for air quality studies: risk perceptions, understandings of air pollution and mobilization in a poor neighborhood in Nairobi, Kenya.

OBJECTIVES: With high urbanization rates, Sub-Saharan Africa is facing growing problems of poor air quality in its cities. We make a case for participatory approaches in air quality studies especially including those living in poor neighborhoods who may be particularly at risk from this trend. STUDY DESIGN: We used collaboration with a community based organization, interviews, focus group discussions and a community forum. METHODS: We conducted a pilot study to assess health risk perceptions of air pollution for civic-minded residents in Mathare, an informal settlement in Nairobi, Kenya. Simultaneously, we involved Mathare residents in measuring levels of PM2.5 and later presented these data at a community forum with the participants of the monitoring study and the focus group discussions. RESULTS: We found that participation in conducting and interpreting air quality studies helped residents improve their understanding of air pollution and also helped them develop responses to it. Initially, participants associated air pollution with a bad odor or discomfort rather than their health, but once the connection to health was made through participation, they sought more information about air quality data and its hazards. Some residents also came up with strategies for coping with their environment and its risks. CONCLUSIONS: These results point to the potential of including participation in air quality monitoring as a way to increase awareness and support local action to address it. Discussion and sharing of results at the local level as well as at a wider policy level will be critical for advocacy to improve air quality.

Influence of molecular ordering on electrical and friction properties of ω-(trans-4-stilbene)alkylthiol self-assembled monolayers on Au(111).

The electrical and friction properties of ω-(trans-4-stilbene)alkylthiol self-assembled monolayers (SAMs) on Au(111) were investigated using atomic force microscopy (AFM) and near edge X-ray absorption fine structure spectroscopy (NEXAFS). The sample surface was uniformly covered with a molecular film consisting of very small grains. Well-ordered and flat monolayer islands were formed after the sample was heated in nitrogen at 120 °C for 1 h. While lattice resolved AFM images revealed a crystalline phase in the islands, the area between islands showed no order. The islands exhibit substantial reduction (50%) in friction, supporting the existence of good ordering. NEXAFS measurements revealed an average upright molecular orientation in the film, both before and after heating, with a narrower tilt-angle distribution for the heated fim. Conductance-AFM measurements revealed a 2 orders of magnitude higher conductivity on the ordered islands than on the disordered phase. We propose that the conductance enhancement is a result of a better π-π stacking between the trans-stilbene molecular units as a result of improved ordering in islands.

Rapid identification of subtype-selective agonists of the somatostatin receptor through combinatorial chemistry.

Nonpeptide agonists of each of the five somatostatin receptors were identified in combinatorial libraries constructed on the basis of molecular modeling of known peptide agonists. In vitro experiments using these selective compounds demonstrated the role of the somatostatin subtype-2 receptor in inhibition of glucagon release from mouse pancreatic alpha cells and the somatostatin subtype-5 receptor as a mediator of insulin secretion from pancreatic beta cells. Both receptors regulated growth hormone release from the rat anterior pituitary gland. The availability of high-affinity, subtype-selective agonists for each of the somatostatin receptors provides a direct approach to defining their physiological functions.

Transfection of insect cell in suspension for efficient baculovirus generation.

Baculovirus (BV) mediated insect cell expression system utilizes transfection as a first step to introduce recombinant baculovirus DNA into insect cells. Many labs are still relying on the conventional liposome based transfection method in adherent culture. Here we describe a more efficient method that can replace the existing method. This method is economical and does not require any special adjustment in existing labs. •An innovative method of transfecting insect cells in suspension using polyethyleneimine (PEI) is described here.•The beauty of this method is minimal intermediate manipulation of culture during transfection and virus generation.•The method significantly reduces the chances of cross contamination of viruses while handling multiple targets and constructs as well as the other microbial contamination.

Remote analysis of physiological data from neurosurgical ICU patients.

Recent technical advances in Internet-based client/server applications and new multimedia communications protocols are enabling the development of cost-effective, platform-independent solutions to the problem of remote access to continuously acquired physiological data. The UCLA Neurosurgery Intensive Care Unit (ICU) has developed a distributed computer system that provides access over the World Wide Web (WWW) to current and previously acquired physiological data, such as intracranial pressure, cerebral perfusion pressure, and heart rate from critical care patients. Physicians and clinical researchers can access these data through personal computers from their offices, from their homes, or even while on the road. The system creates and continuously updates a database of all monitored parameters in data formats that can readily be used for further clinical studies. This paper describes an extension to this system that allows for remote interaction with and analysis of the data via the WWW. Physicians can now pose a limited, predefined set of clinically relevant questions to the system without having to be at the patient's bedside.

Face-selective spectral changes in the human fusiform gyrus.

OBJECTIVE: To characterize ventral occipitotemporal and prefrontal EEG during cognitive processing. METHODS: Depth probes were implanted for seizure localization in 16 pharmaco-resistant epileptics. Probes penetrated from middle temporal through fusiform to lingual gyrus, and from inferior frontal to anterior cingulate gyrus. Event-related potentials (ERPs) and event-related spectral power (ERSP) were calculated during delayed recognition for faces or words. RESULTS: Face stimuli evoked a broadband fusiform ERSP increase from 5 to 45 Hz at 150-210 ms after stimulus onset. This ERSP increase was immediately followed by an ERSP decrease in the same region from 300 to 1000 ms. Both the early increased ERSP and the late decreased ERSP, were greater for faces than words. Simultaneous with the late temporal ERSP decrease, the prefrontal depth EEG displayed a low frequency (5-12 Hz) ERSP increase to face and word stimuli. CONCLUSION: Early temporal ERSP increases occur at a time when the fusiform gyrus is thought to contribute to face processing. This increase is also reflected in spectral analysis of the ERP, but the late temporal ERSP decrease and frontal ERSP increase are not. Thus, intracranial recordings in humans demonstrate event-related fluctuations in EEG spectral power with clear anatomical, temporal and cognitive specificity.

Alcohol effects on movement-related potentials: a measure of impulsivity?

OBJECTIVE: To assess the effects of acute alcohol intoxication on lateralized readiness potential (LRP), a central measure of movement-related brain activity, and the potential association of such effects with personality measures. METHOD: Male volunteers (N = 12) alternated responding hands during a "go/no go" verbal recognition task across all four sessions of the balanced placebo design in which beverage content (either juice only or a vodka and juice mixture that raised the average blood alcohol concentration to 0.045%) was crossed with instructions as to beverage content. RESULTS: Whereas the instructions had no effect on behavioral (response accuracy and reaction time) and physiological (LRP) measures, alcohol decreased reaction times adjusted for psychometer speed. As expected, large LRPs were recorded on "go" trials and were not affected by the beverage. However, the "no go" words that did not require and did not evoke motor responses, also evoked significant LRPs under alcohol but not placebo. Since only trials with correct responses and correct abstentions from responses were included in the averages, the motor preparation was not completed and was terminated before the motor response on "no go" trials. Similarly, there was a decrease in spectral power of the movement-related mu-rhythm on "no go" trials under alcohol. CONCLUSIONS: Alcohol may result in disinhibition such that the "response execution" process is activated based on very preliminary stimulus evaluation. This alcohol-induced brain activity signaling premature motor preparation exhibited correlation trends with personality traits related to impulsivity, hyperactivity and antisocial tendencies, thus concurring with other evidence that indicates commonalities between alcoholism and impulsivity, disinhibition and antisocial behaviors. The LRP on "no go" trials could potentially be used as a psychological index of the impulsiveness induced by alcohol intoxication.

Remote access to neurosurgical ICU physiological data using the World Wide Web.

There is a significant demand by physicians and clinical researchers for remote access to continuously acquired physiological patient data. Until recently such access was technically unfeasible. However, with the recent development of Internet-based World Wide Web (WWW) client/server applications and underlying communication protocols, there is now a real possibility for the development of cost-effective, platform independent solutions to this problem. We have devised a way using existing WWW tools and minimal startup costs to provide access to current as well as previously acquired physiological patient data. Physicians and clinical researchers can obtain access to these data through personal computers located in the office, at home or even through portable computers while traveling to conferences or while on vacation.

Insect cell culture in reagent bottles.

Growing insect cells with high air space in culture vessel is common from the early development of suspension cell culture. We believed and followed it with the hope that it allows sufficient air for optimal cell growth. However, we missed to identify how much air exactly cells need for its growth and multiplication. Here we present the innovative method that changed the way we run insect cell culture. The method is easy to adapt, cost-effective and useful for both academic and industrial research labs. We believe this method will revolutionize the way we run insect cell culture by increasing throughput in a cost-effective way. In our study we identified:•Insect cells need to be in suspension; air space in culture vessel and type of culture vessel is of less importance. Shaking condition that introduces small air bubbles and maintains it in suspension for longer time provides better oxygen transfer in liquid. For this, high-fill volume in combination with speed and shaking diameter are important.•Commercially available insect cells are not fragile as original isolates. These cells can easily withstand higher shaking speed.•Growth condition in particular lab set-up needs to be optimized. The condition used in one lab may not be optimum for another lab due to different incubators from different vendors.

Phylogenetic ordinal placement based on rDNA sequences of the freshwater genera Ophioceras and Pseudohalonectria.

The ordinal placement of two closely related freshwater genera, Ophioceras and Pseudohalonectria, was assessed by using phylogenetic analysis of morphological characters, partial sequences of the large subunit ribosomal DNA and restriction site variations in the internal transcribed spacer (ITS). The two genera have some morphological features that are used to define taxa in both the Sordariales and Diaporthales, and, hence, their phylogenetic relationships are unclear. Equally weighted analyses of thirty-eight morphological characters produced unresolved phylogenetic trees and unequivocal conclusions could not be drawn based on the morphological data. The polymerase chain reaction-amplified ITS region was variable in length between the two genera and restriction sites in the ITS region were determined. Analysis of variation in restriction sites in the ITS region placed Ophioceras and Pseudohalonectria in one clade with taxa sampled from Sordariales. About 350 basepairs of DNA sequence from the 5' end of the large subunit rDNA were also determined. In phylogenetic analysis of the sequence data with Hypocrea lutea and Nectria cinnabarina as outgroups, Ophioceras and Pseudohalonectria showed a closer relationship to Neurospora crassa, Schizothecium sp., and Sordaria fimicola of the Sordariales than to Cryphonectria parasitica and Endothia gyrosa of the Diaporthales.

Timing and localization of movement-related spectral changes in the human peri-Rolandic cortex: intracranial recordings.

Event-related spectral power (ERSP) was measured from intracranial EEG and used to characterize the time-course and localization of the Rolandic mu rhythms in 12 patients during the delayed recognition of words or faces (DR) and the discrimination of simple lateralized visual targets (LVD). On each trial, the subject decided whether to make manual response (Go) or not (NoGo). ERSP increased on both Go and NoGo trials in peri-Rolandic regions of all subjects with a peak latency of approximately 330-ms poststimulus and duration of 260 ms during the DR task. The peak of this ERSP increase preceded movement by approximately 300 ms. All subjects produced a subsequent movement specific ERSP decrease of peri-Rolandic mu rhythms (starting approximately 90 ms before the average reaction time) with an peak latency of approximately 800 ms and duration of approximately 520 ms. The LVD task produced bilateral movement-selective readiness potentials and reproduced the movement-specific late ERSP decreases seen in the DR task (strongest from 7-24 Hz). Furthermore, the LVD task demonstrated that the late movement-related ERSP decrease is larger for the contralateral hand. However, the LVD task did not consistently reproduce the early ERSP increase seen in the DR task. Movement-related ERSP decreases were widespread, occurring in pre- and post-Rolandic as well as primary-motor, supplemental motor, and cingulate cortical regions. Other cortical areas including frontal, temporal, and occipital regions did not show movement-related ERSP changes. Peri-Rolandic ERSP decreases in mu rhythms correlate with the generation of a motor command. The early increases in mu may reflect a transient state of motor inhibition just prior to motor execution.

Early widespread cortical distribution of coherent fusiform face selective activity.

Intracranial EEG was analyzed from 16 pharmaco-resistant epilepsy patients. Subjects participated in memory tasks for faces and/or words. Face-selective coherence increases were found between the fusiform gyrus and temporal, parietal, and frontal cortices at 160-230 ms poststimulus onset. Word stimuli elicited weak or negligible response at the same latency. Phase lag increased monotonically with distance from the fusiform region. The slope was consistent with conduction velocities of myelinated cortico-cortical pathways. These results suggest that the contribution of the fusiform gyrus to face processing at around 200 ms poststimulus onset is rapidly projected to widespread cortical regions.