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Growth- and health-promoting bacteria can boost crop productivity in a sustainable way. Pseudomonas simiae WCS417 is such a bacterium that efficiently colonizes roots, modifies the architecture of the root system to increase its size, and induces systemic resistance to make plants more resistant to pests and pathogens. Our previous work suggested that WCS417-induced phenotypes are controlled by root cell-type-specific mechanisms. However, it remains unclear how WCS417 affects these mechanisms. In this study, we transcriptionally profiled five Arabidopsis thaliana root cell types following WCS417 colonization. We found that the cortex and endodermis have the most differentially expressed genes, even though they are not in direct contact with this epiphytic bacterium. Many of these genes are associated with reduced cell wall biogenesis, and mutant analysis suggests that this downregulation facilitates WCS417-driven root architectural changes. Furthermore, we observed elevated expression of suberin biosynthesis genes and increased deposition of suberin in the endodermis of WCS417-colonized roots. Using an endodermal barrier mutant, we showed the importance of endodermal barrier integrity for optimal plant-beneficial bacterium association. Comparison of the transcriptome profiles in the two epidermal cell types that are in direct contact with WCS417—trichoblasts that form root hairs and atrichoblasts that do not—implies a difference in potential for defense gene activation. While both cell types respond to WCS417, trichoblasts displayed both higher basal and WCS417-dependent activation of defense-related genes compared with atrichoblasts. This suggests that root hairs may activate root immunity, a hypothesis that is supported by differential immune responses in root hair mutants. Taken together, these results highlight the strength of cell-type-specific transcriptional profiling to uncover "masked" biological mechanisms underlying beneficial plant-microbe associations. This study investigates how the epiphytic plant-beneficial bacterium Pseudomonas simiae WCS417 affects different root cell types of Arabidopsis thaliana using cell-type-specific transcriptomics. Bioinformatic analysis and further experimental validation demonstrate that WCS417 alters cell wall biogenesis and suberin deposition inside the root, potentially facilitating root development and bacterial colonization. Furthermore, this study reveals a role of root hairs in immune activation. [ABSTRACT FROM AUTHOR]

Plants have incredible developmental plasticity, enabling them to respond to a wide range of environmental conditions. Among these conditions is the presence of plant growth-promoting rhizobacteria (PGPR) in the soil. Recent studies show that PGPR affect Arabidopsis thaliana root growth and development by modulating cell division and differentiation in the primary root and influencing lateral root development. These effects lead to dramatic changes in root system architecture that significantly impact aboveground plant growth. Thus, PGPR may promote shoot growth via their effect on root developmental programs. This review focuses on contextualizing root developmental changes elicited by PGPR in light of our understanding of plant–microbe interactions and root developmental biology. [ABSTRACT FROM AUTHOR]

Stem cells are defined by their ability to self-renew and produce daughter cells that proliferate and mature. These maturing cells transition from a proliferative state to a terminal state through the process of differentiation. In the Arabidopsis thaliana root the transcription factors SCARECROW and SHORTROOT regulate specification of the bipotent stem cell that gives rise to cortical and endodermal progenitors. Subsequent progenitor proliferation and differentiation generate mature endodermis, marked by the Casparian strip, a cell-wall modification that prevents ion diffusion into and out of the vasculature. We identified a transcription factor, MYB DOMAIN PROTEIN 36 (MYB36), that regulates the transition from proliferation to differentiation in the endodermis. We show that SCARECROW directly activates MYB36 expression, and that MYB36 likely acts in a feed-forward loop to regulate essential Casparian strip formation genes. We show that myb36 mutants have delayed and defective barrier formation as well as extra divisions in the meristem. Our results demonstrate that MYB36 is a critical positive regulator of differentiation and negative regulator of cell proliferation. [ABSTRACT FROM AUTHOR]

A growing literature suggests that juvenile arrests perpetuate offending and increase the likelihood of future arrests. The effect on subsequent arrests is generally regarded as a product of the perpetuation of criminal offending. However, increased rearrest also may reflect differential law enforcement behavior. Using longitudinal data from the Project on Human Development in Chicago Neighborhoods (PHDCN) together with official arrest records, the current study estimates the effects of first arrests on both reoffending and rearrest. Propensity score methods were used to control differences between arrestees and nonarrestees and to minimize selection bias. Among 1,249 PHDCN youths, 58 individuals were first arrested during the study period; 43 of these arrestees were successfully matched to 126 control cases that were equivalent on a broad set of individual, family, peer, and neighborhood factors. We find that first arrests increased the likelihood of both subsequent offending and subsequent arrest, through separate processes. The effects on rearrest are substantially greater and are largely independent of the effects on reoffending, which suggests that labels trigger 'secondary sanctioning' processes distinct from secondary deviance processes. Attempts to ameliorate deleterious labeling effects should include efforts to dampen their escalating punitive effects on societal responses. [ABSTRACT FROM AUTHOR]

Genome-scale studies hold great promise for revealing novel plant biology. Because of the complexity of these techniques, numerous considerations need to be made before embarking on a study. Here we focus on the Arabidopsis model system because of the wealth of available genome-scale data. Many approaches are available that provide genome-scale information regarding the state of a given organism (e.g. genomics, epigenomics, transcriptomics, proteomics, metabolomics interactomics, ionomics, phenomics, etc.). Integration of all of these types of data will be necessary for a comprehensive description of Arabidopsis. In this review we propose that ‘triangulation’ among transcriptomics, proteomics and metabolomics is a meaningful approach for beginning this integrative analysis and uncovering a systems level perspective of Arabidopsis biology. [Copyright &y& Elsevier]

Diagnosing and treating depression in a primary care practice is an important, yet difficult task, especially for safety-net practices serving the uninsured. In the United States healthcare system, there is a mismatch between the need for mental health care and access to services. This disparity is most striking among the uninsured. Mental health disorders are more prevalent among the uninsured, and even when diagnosed with mental illness, they are less likely to obtain necessary treatment than insured patients. Given the increasing burden of depression on society, growing numbers of uninsured and negative repercussions of untreated mental illness, improvements in screening and management protocols are becoming more important in primary care practices serving this population. The quality of depression treatment at commercial and public insurance plans in New York City (NYC) and New York State (NYS) were compared to that of the East Harlem Health Outreach Partnership (EHHOP), the student-run clinic of the Mount Sinai School of Medicine. Based on the comparison, the study made recommendations for an integrated, on-site mental health service program at the community health clinic. A cohort of 49 depressed patients were evaluated and treated at the EHHOP clinic. The quality of the mental health care was evaluated according to variables from the Healthcare Effectiveness Data and Information Set (HEDIS). Indicators of quality included demographics, method of diagnosis, type of pharmacological treatment, referral to specialty care, patient adherence to follow-up care and adherence to pharmacologic treatment. When compared to insured patients in NYS, more EHHOP patients had the appropriate number of physician contacts after being diagnosed with depression than patients with commercial health plans ( P = 0.008) and Medicaid ( P = 0.09). Similarly, a greater number of EHHOP patients had better acute phase ( P = 0.001; P = 0.096) and continuous phase ( P = 0.049; P = 0.88) pharmacologic treatment than patients with commercial health plans and Medicaid, respectively. EHHOP meets and, in some areas, exceeds the quality of depression treatment when compared to insured populations. Even though EHHOP already surpasses these indicators, the clinic can improve its diagnostic capabilities, prescription medication adherence, and referral care follow-through by creating an on-site mental health clinic. [ABSTRACT FROM AUTHOR]

Endophytic fungi are found within the roots of healthy plants, but their function is poorly understood. In this issue, Hiruma et al. demonstrate that, under phosphate-limiting conditions, the endophytic fungus, Colletotrichum tofieldiae , provides growth-promoting and fitness benefits to Arabidopsis , but the plant must restrict fungal growth or risk pathogenesis. [ABSTRACT FROM AUTHOR]

The NF-KB-related transcription factor, Dorsal, forms a nuclear concentration gradient in the early Drosophila embryo, patterning the dorsal-ventral (DV) axis to specify mesoderm, neurogenic ectoderm, and dorsal ectoderm cell fates. The concentration of nuclear Dorsal is thought to determine these patterning events; however, the levels of nuclear Dorsal have not been quantified previously. Furthermore, existing models of Dorsal-dependent germ layer specification and patterning consider steady-state levels of Dorsal relative to target gene expression patterns, yet both Dorsal gradient formation and gene expression are dynamic. We devised a quantitative imaging method to measure the Dorsal nuclear gradient while simultaneously examining Dorsal target gene expression along the DV axis. Unlike observations from other insects such as Tribolium, we find the Dorsal gradient maintains a constant bell-shaped distribution during embryogenesis. We also find that some classical Dorsal target genes are located outside the region of graded Dorsal nuclear localization, raising the question of whether these genes are direct Dorsal targets. Additionally, we show that Dorsal levels change in time during embryogenesis such that a steady state is not reached. These results suggest that the multiple gene expression outputs observed along the DV axis do not simply reflect a steady-state Dorsal nuclear gradient. Instead, we propose that the Dorsal gradient supplies positional information throughout nuclear cycles 10-14, providing additional evidence for the idea that compensatory combinatorial interactions between Dorsal and other factors effect differential gene expression along the DV axis. [ABSTRACT FROM AUTHOR]

Abstract: In early Drosophila embryos, the transcription factor Dorsal regulates patterns of gene expression and cell fate specification along the dorsal–ventral axis. How gene expression is produced within the broad lateral domain of the presumptive neurogenic ectoderm is not understood. To investigate transcriptional control during neurogenic ectoderm specification, we examined divergence and function of an embryonic cis-regulatory element controlling the gene short gastrulation (sog). While transcription factor binding sites are not completely conserved, we demonstrate that these sequences are bona fide regulatory elements, despite variable regulatory architecture. Mutation of conserved sequences revealed that putative transcription factor binding sites for Dorsal and Zelda, a ubiquitous maternal transcription factor, are required for proper sog expression. When Zelda and Dorsal sites are paired in a synthetic regulatory element, broad lateral expression results. However, synthetic regulatory elements that contain Dorsal and an additional activator also drive expression throughout the neurogenic ectoderm. Our results suggest that interaction between Dorsal and Zelda drives expression within the presumptive neurogenic ectoderm, but they also demonstrate that regulatory architecture directing expression in this domain is flexible. We propose a model for neurogenic ectoderm specification in which gene regulation occurs at the intersection of temporal and spatial transcription factor inputs. [Copyright &y& Elsevier]

Focuses on the importance of the right theory of speech to reading researchers and reading teachers. Assumptions underlying the conventional and unconventional theories of speech; Application of the particulate principle in language; Disadvantages of using the horizontal theory on speech and reading; Factors considered in particulate communication.

Focuses on the basis of voice onset time (VOT) relative to supraglottal articulation. Boundary values between voiced and voiceless initial stops of English; Features of the synthetic speech patterns; Increase in the VOT value at the boundary between synthetic syllables.

Seeks to provide data that supports the argument that the consonantal elements of language should be immediately phonetic. Methodology utilized in the study; How variations in the evidence for distinct sources affect the growth or decline of their phonetic and auditory representations; Results and conclusion of the research.

Experiments with synthetic speech produced by the Pattern Playback indicated that the voiced stops in initial position could be made to sound like their voiceless counterparts by cutting back the beginning of the first-formant transition. Normally, the cutback of the first formant raises its starting frequency and also delays the time at which it begins relative to the other two formants. Both these changes appeared, in general, to be necessary. With certain combinations of stop and back vowel, however, a delay in the onset of the first formant was by itself sufficient to produce a strong voiceless effect. Substituting noise for harmonics in the transitions of the second and third formants (for the duration of the first-formant cutback) increased the impression of voicelessness over that obtained with cutback alone.In judging stimuli that lay near phoneme boundaries, many listeners demonstrated what appeared to be a very high degree of acuity. It is possible that this is the result of long experience in the use of the language and thus represents an effect of learning on perception. [ABSTRACT FROM PUBLISHER]

The article presents a number of cues for the distinction between voiced and voiceless stops in initial position. Studies with synthetic speech produced by the Pattern Playback showed that the voiced stops in initial position could be made to sound like their voiceless counterparts by cutting back the beginning of the first-formant transition. Normally, the cutback of the first formant raises its starting frequency and also delays the time at which it begins relative to the other two formants. Both these changes appeared, in general, to be necessary. With certain combinations of stop and back vowel, however, a delay in the onset of the first formant was by itself sufficient to produce a strong voiceless effect.

Establishing polarized surfaces enables cells to carry out specialized tasks. In this issue, Lee et al. present a mechanism for cell polarization in which localized peroxidases are used to position the Casparian strip, a diffusion barrier deposited between endodermal cells in plant roots. [Copyright &y& Elsevier]

Pairs of RNA molecules transcribed from partially or entirely complementary loci are called cis-natural antisense transcripts (cis-NATs), and they play key roles in the regulation of gene expression in many organisms. A promising experimental tool for profiling sense and antisense transcription is strand-specific RNA sequencing (ssRNA-seq). To identify cis-NATs using ssRNA-seq, we developed a new computational method based on a model comparison framework that incorporates the inherent variable efficiency of generating perfectly strand-specific libraries. Applying the method to new ssRNA-seq data from whole-root and cell-type"specific Arabidopsis libraries confirmed most of the known cis-NAT pairs and identified 918 additional cis-NAT pairs. Newly identified cis-NAT pairs are supported by polyadenylation data, alternative splicing patterns, and RT-PCR validation. We found 209 cis-NAT pairs that have opposite expression levels in neighboring cell types, implying cell-type"specific roles for cis-NATs. By integrating a genome-wide epigenetic profile of Arabidopsis, we identified a unique chromatin signature of cis-NATs, suggesting a connection between cis-NAT transcription and chromatin modification in plants. An analysis of small-RNA sequencing data showed that 1/44% of cis-NAT pairs produce putative cis-NAT"induced siRNAs. Taken together, our data and analyses illustrate the potential for multifaceted regulatory roles of plant cis-NATs. [ABSTRACT FROM AUTHOR]

Certain types of cellular differentiation are probabilistic and transient. In such systems individual cells can switch to an alternative state and, after some time, switch back again. In Bacillus subtilis, competence is an example of such a transiently differentiated state associated with the capability for DNA uptake from the environment. Individual genes and proteins underlying differentiation into the competent state have been identified, but it has been unclear how these genes interact dynamically in individual cells to control both spontaneous entry into competence and return to vegetative growth. Here we show that this behaviour can be understood in terms of excitability in the underlying genetic circuit. Using quantitative fluorescence time-lapse microscopy, we directly observed the activities of multiple circuit components simultaneously in individual cells, and analysed the resulting data in terms of a mathematical model. We find that an excitable core module containing positive and negative feedback loops can explain both entry into, and exit from, the competent state. We further tested this model by analysing initiation in sister cells, and by re-engineering the gene circuit to specifically block exit. Excitable dynamics driven by noise naturally generate stochastic and transient responses, thereby providing an ideal mechanism for competence regulation. [ABSTRACT FROM AUTHOR]

Discusses experiments designed to discover if CV transitions are also included by the listener in determining the effective duration of the "vowel." Investigations into the perceptual relevance of vowel duration that have employed patterns of synthetic speech in which only the steady-state portions of syllables have been used as the variable; Contribution of syllable-initial formant transitions to the vowel duration on which the voicing of a stop in syllable-final position can be made to depend.

Root branching in plants relies on the de novo formation of lateral roots. These are initiated from founder cells, triggering new formative divisions that generate lateral root primordia (LRP). The LRP size and shape depends on the balance between positive and negative signals that control cell proliferation., The mechanisms controlling proliferation potential of LRP cells remains poorly understood. We found that Arabidopsis thaliana MYB36, which have been previously shown to regulate genes required for Casparian strip formation and the transition from proliferation to differentiation in the primary root, plays a new role in controlling LRP development at later stages., We found that MYB36 is a novel component of LR development at later stages. MYB36 was expressed in the cells surrounding LRP where it controls a set of peroxidase genes, which maintain reactive oxygen species (ROS) balance. This was required to define the transition between proliferating and arrested cells inside the LRP, coinciding with the change from flat to dome-shaped primordia. Reducing the levels of hydrogen peroxide (H2O2) in myb36-5 significantly rescues the mutant phenotype., Our results uncover a role for MYB36 outside the endodermis during LRP development through a mechanism analogous to regulating the proliferation/differentiation transition in the root meristem. [ABSTRACT FROM AUTHOR]

Abstract: Children and adolescents in the U.S. and worldwide are commonly exposed to traumatic events, yet practitioners treating these young people to reduce subsequent psychological harm may not be aware of—or use—interventions based on the best available evidence. This systematic review evaluated interventions commonly used to reduce psychological harm among children and adolescents exposed to traumatic events. Guide to Community Preventive Services (Community Guide) criteria were used to assess study design and execution. Meta-analyses were conducted, stratifying by traumatic exposures. Evaluated interventions were conducted in high-income economies, published up to March 2007. Subjects in studies were ≤21 years of age, exposed to individual/mass, intentional/unintentional, or manmade/natural traumatic events. The seven evaluated interventions were individual cognitive–behavioral therapy, group cognitive behavioral therapy, play therapy, art therapy, psychodynamic therapy, and pharmacologic therapy for symptomatic children and adolescents, and psychological debriefing, regardless of symptoms. The main outcome measures were indices of depressive disorders, anxiety and posttraumatic stress disorder, internalizing and externalizing disorders, and suicidal behavior. Strong evidence (according to Community Guide rules) showed that individual and group cognitive–behavioral therapy can decrease psychological harm among symptomatic children and adolescents exposed to trauma. Evidence was insufficient to determine the effectiveness of play therapy, art therapy, pharmacologic therapy, psychodynamic therapy, or psychological debriefing in reducing psychological harm. Personnel treating children and adolescents exposed to traumatic events should use interventions for which evidence of effectiveness is available, such as individual and group cognitive–behavior therapy. Interventions should be adapted for use in diverse populations and settings. Research should be pursued on the effectiveness of interventions for which evidence is currently insufficient. [Copyright &y& Elsevier]

Abstract: In the present study we analyzed both photosynthetic and UV-B absorbing pigment variations in Polylepis tarapacana (Rosaceae) during two contrasting seasons (winter and summer) at two altitudes (4300 and 5000m a.s.l.) in the Sajama volcano (Oruro, Bolivia). UV-B absorbing pigments, chlorophyll a, b and carotenoids contents as well as the chlorophyll a to chlorophyll b ratio showed clear differences in both seasons. UV-B absorbing pigments, total chlorophyll and chlorophyll a contents as well as chlorophyll a/b values were higher in winter than in summer at both altitudes, while chlorophyll b content and the total chlorophyll to carotenoids ratio showed an opposite pattern. Carotenoids content exhibited not only an increase with altitude but also a significant variation between seasons, the highest value being recorded in winter. We discuss the results in relation to the radiation regime of the Sajama region rather than to the water status of the plant studied, since the latter was similar for both seasons and altitudes. [Copyright &y& Elsevier]

Primary auditory cortex (PAC), located in Heschl’s gyrus (HG), is the earliest cortical level at which sounds are processed. Standard theories of speech perception assume that signal components are given a representation in PAC which are then matched to speech templates in auditory association cortex. An alternative holds that speech activates a specialized system in cortex that does not use the primitives of PAC. Functional magnetic resonance imaging revealed different brain activation patterns in listening to speech and nonspeech sounds across different levels of complexity. Sensitivity to speech was observed in association cortex, as expected. Further, activation in HG increased with increasing levels of complexity with added fundamentals for both nonspeech and speech stimuli, but only for nonspeech when separate sources (release bursts/fricative noises or their nonspeech analogs) were added. These results are consistent with the existence of a specialized speech system which bypasses more typical processes at the earliest cortical level. [ABSTRACT FROM AUTHOR]

The reactions of arylbiguanides with acetyacetone derivatives were used to obtain N-(pyrimidin-2-yl)- N′-arylguanidines, and the reactions with acetoacetic ester derivatives (depending on the structure of the keto esters), N-aryl- N′-(4-oxo-3,4-dihydropyrimidin-2-yl)guanidines or 2-amino-4-arylamino-6-aryl(heteryl)-sulfanylmethylene-1,3,5-triazines. The N-aryl- N′-heterylguanidines formed by the reactions with anhydrides, acyl halides, and aryl isocyanates give rise to the corresponding triaza derivatives. [ABSTRACT FROM AUTHOR]

ABSTRACTThe Polylepis tarapacana forests found in Bolivia are unique with respect to their altitudinal distribution (4200–5200 m). Given the extreme environmental conditions that characterize these altitudes, this species has to rely on distinct mechanisms to survive stressful temperatures. The purpose of this study was to determine low-temperature resistance mechanisms in P. tarapacana. Tissue was sampled for carbohydrate and proline contents and micro-climatic measurements were made at two altitudes, 4300 and 4850 m, during both the dry cold and wet warm seasons. Supercooling capacity (-3 to -6 °C for the cold dry and -7 to -9 °C for the wet warm season) and injury temperatures (-18 to -23 °C for both seasons), determined in the laboratory, indicate that P. tarapacana is a frost-tolerant species. On the other hand, an increase in supercooling capacity, as the result of significant increase in total soluble sugar and proline contents, occurs during the wet warm season as a consequence of higher metabolic activity. Hence, P. tarapacana, a frost-tolerant species during the colder unfavourable season, is able to avoid freezing during the more favourable season when minimum night-time temperatures are not as extreme. [ABSTRACT FROM AUTHOR]

Presents a study which was conducted to investigate the location and extent of the functional disruption in neural systems which causes dyslexia. Methodologyy used to conduct the study; Results of the study.

In previous studies of the acoustic cues that may be used in the identification of English consonants, it has been found that, at least for certain classes of consonant, there is a strong tendency for listeners to hear speech sounds in a categorical fashion. The measures of discrimination showed that subjects were in fact more sensitive to change in the region of the phoneme boundary than at other points in the continuum of change. Researchers are concerned here only with groups of sounds in which change with respect to a single acoustic dimension is a sufficient cue for phonemic differences.

To identify the influence of pediatric cochlear implantation on long term communication modality, education, and income. A telephone survey was conducted with 56 young adults who had received cochlear implants (CI) as children. The participants were, on average, 10.6 (SD = 64) when they received their CI and 21 (SD = 2.29) when they participated in this study. All of the participants used a unilateral CI at the time of the survey. Where applicable, survey results were compared to the general population of similar aged individuals in Ontario using chi-squared tests of proportionality. Participants (49/56, 88%) indicated that they used their CI all waking hours and 75% (42/56) reported using spoken language as their primary mode of communication. They attended post-secondary school at higher rates than the general population (χ2(1) = 14.35, p <.001); a wide range of study areas were identified with a greater proportion involved in fine arts than the general population (χ 2 (1) = 25.50, p <.001). The rates of employment in this group were below general rates (χ2(1) = 21.87, p <.001). However, those who were employed reported salaries similar to their hearing peers. The findings from this study suggest that young adults who received a unilateral CI in childhood typically continue to use their CIs to support spoken language. Their increased rates of post-secondary education are encouraging and they may be choosing unique areas of study. Longer term studies are required to further investigate lower rates of employment in this cohort. [ABSTRACT FROM AUTHOR]