The Impact of Terrain on Strategy

This is a subject that has won battles, campaigns, and wars for those who respected and under­stood it; on the other hand, its neglect has brought superior forces to their knees. It is one of the most important subjects in the wide spectrum of military strategy, but also one of the least esteemed and most frequently overlooked

The aromatic amino acid hydroxylase genes AAH1 and AAH2 in Toxoplasma gondii contribute to transmission in the cat

The Toxoplasma gondii genome contains two aromatic amino acid hydroxylase genes, AAH1 and AAH2 encode proteins that produce L-DOPA, which can serve as a precursor of catecholamine neurotransmitters. It has been suggested that this pathway elevates host dopamine levels thus making infected rodents less fearful of their definitive Felidae hosts. However, L-DOPA is also a structural precursor of melanins, secondary quinones, and dityrosine protein crosslinks, which are produced by many species. For example, dityrosine crosslinks are abundant in the oocyst walls of Eimeria and T. gondii, although their structural role has not been demonstrated, Here, we investigated the biology of AAH knockout parasites in the sexual reproductive cycle within cats. We found that ablation of the AAH genes resulted in reduced infection in the cat, lower oocyst yields, and decreased rates of sporulation. Our findings suggest that the AAH genes play a predominant role during infection in the gut of the definitive feline host

Field-scale validation of an automated soil nitrate extraction and measurement system

One of the many gaps that needs to be solved by precision agriculture technologies is the availability of an economic, automated, on-the-go mapping system that can be used to obtain intensive and accurate ‘real-time’ data on the levels of nitrate nitrogen (NO3–N) in the soil. A soil nitrate mapping system (SNMS) has been developed to provide a way to collect such data. This study was done to provide extensive field-scale validation testing of the system’s nitrate extraction and measurement sub-unit (NEMS) in two crop (wheat and carrot) production systems. Field conditions included conventional tillage (CT) versus no tillage (NT), inorganic versus organic fertilizer application, four soil groups and three points in time throughout the season. Detailed data analysis showed that: (i) the level of agreement, as measured by root mean squared error (RMSE), mean absolute error (MAE) and coefficient of efficiency (CE), between NEMS soil NO3–N and standard laboratory soil NO3–N measurements was excellent; (ii) at the field-scale, there was little practical difference when using either integer or real number data processing; (iii) regression equations can be used to enable field measurements of soil NO3–N using the NEMS to be obtained with laboratory accuracy; (iv) future designs of the SNMS’s control system can continue to use cheaper integer chip technology for processing the nitrate ion-selective electrode (NO3 -–ISE) readings; and (v) future designs of the SNMS would not need a soil moisture sensor, ultimately saving on manufacturing costs of a more simple syste

A Mechanism Linking Two Known Vulnerability Factors for Alcohol Abuse: Heightened Alcohol Stimulation and Low Striatal Dopamine D2 Receptors

Alcohol produces both stimulant and sedative effects in humans and rodents. In humans, alcohol abuse disorder is associated with a higher stimulant and lower sedative responses to alcohol. Here, we show that this association is conserved in mice and demonstrate a causal link with another liability factor: low expression of striatal dopamine D2 receptors (D2Rs). Using transgenic mouse lines, we find that the selective loss of D2Rs on striatal medium spiny neurons enhances sensitivity to ethanol stimulation and generates resilience to ethanol sedation. These mice also display higher preference and escalation of ethanol drinking, which continues despite adverse outcomes. We find that striatal D1R activation is required for ethanol stimulation and that this signaling is enhanced in mice with low striatal D2Rs. These data demonstrate a link between two vulnerability factors for alcohol abuse and offer evidence for a mechanism in which low striatal D2Rs trigger D1R hypersensitivity, ultimately leading to compulsive-like drinkingFil: Bocarsly, Miriam E.. National Institutes of Health; Estados UnidosFil: da Silva e Silva, Daniel. National Institutes of Health; Estados UnidosFil: Kolb, Vanessa. National Institutes of Health; Estados UnidosFil: Luderman, Kathryn D.. National Institutes of Health; Estados UnidosFil: Shashikiran, Sannidhi. National Institutes of Health; Estados UnidosFil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Sibley, David R.. National Institutes of Health; Estados UnidosFil: Dobbs, Lauren K.. National Institutes of Health; Estados Unidos. University of Texas at Austin; Estados UnidosFil: Álvarez, Verónica Alicia. National Institutes of Health; Estados Unido

Changes in spatiotemporal gait variables over time during a test of functional capacity after stroke

<p>Abstract</p> <p>Background</p> <p>Gait dysfunction and fatigue are common post-stroke, though it is unclear how extended walking activity, as would be performed during activities of daily living, may change over time. The purpose of this study was to examine if spatial and temporal gait variables deteriorate during an extended bout of walking in a test of functional capacity after stroke.</p> <p>Methods</p> <p>24 community dwelling, independently ambulating individuals greater than 3 months after stroke performed the Six-Minute Walk Test (6MWT). Participants walked over a pressure-sensitive mat on each pass of the 30 m course which recorded spatial and temporal parameters of gait. Mean gait speed and temporal symmetry ratio during each two-minute interval of the 6MWT were examined. Additional post hoc analyses examined the incidence of rests during the 6MWT and changes in gait speed and symmetry.</p> <p>Results</p> <p>On average, participants demonstrated a 3.4 ± 6.5 cm/s decrease in speed over time (p= 0.02). Participants who rested were also characterized by increased asymmetry in the final two minutes (p= 0.05). 30% of participants rested at some point during the test, and if a rest was taken, duration increased in the final two minutes (p= 0.001). Examination of factors which may have been associated with resting indicated that resters had poorer balance (p= 0.006) than non-resting participants.</p> <p>Conclusion</p> <p>This study supports previous findings establishing that walking performance after stroke declines over relatively short bouts of functionally-relevant ambulation. Such changes may be associated with both cardiorespiratory and muscular fatigue mechanisms that influence performance. The findings also indicate that rest duration should be routinely quantified during the 6MWT after stroke, and consequently, further research is necessary to determine how to interpret 6MWT scores when resting occurs.</p

Overexpression screen of interferon-stimulated genes identifies RARRES3 as a restrictor of Toxoplasma gondii infection

Toxoplasma gondii is an important human pathogen infecting an estimated one in three people worldwide. The cytokine interferon gamma (IFNγ) is induced during infection and is critical for restricting T. gondii growth in human cells. Growth restriction is presumed to be due to the induction of interferon-stimulated genes (ISGs) that are upregulated to protect the host from infection. Although there are hundreds of ISGs induced by IFNγ, their individual roles in restricting parasite growth in human cells remain somewhat elusive. To address this deficiency, we screened a library of 414 IFNγ induced ISGs to identify factors that impact T. gondii infection in human cells. In addition to IRF1, which likely acts through the induction of numerous downstream genes, we identified RARRES3 as a single factor that restricts T. gondii infection by inducing premature egress of the parasite in multiple human cell lines. Overall, while we successfully identified a novel IFNγ induced factor restricting T. gondii infection, the limited number of ISGs capable of restricting T. gondii infection when individually expressed suggests that IFNγ-mediated immunity to T. gondii infection is a complex, multifactorial process

Cultural Theories of Postpartum Bleeding in Matlab, Bangladesh: Implications for Community Health Intervention

Early recognition can reduce maternal disability and deaths due to postpartum haemorrhage. This study identified cultural theories of postpartum bleeding that may lead to inappropriate recognition and delayed care-seeking. Qualitative and quantitative data obtained through structured interviews with 149 participants living in Matlab, Bangladesh, including women aged 18-49 years, women aged 50+ years, traditional birth attendants (TBAs), and skilled birth attendants (SBAs), were subjected to cultural domain. General consensus existed among the TBAs and lay women regarding signs, causes, and treatments of postpartum bleeding (eigenvalue ratio 5.9, mean competence 0.59, and standard deviation 0.15). Excessive bleeding appeared to be distinguished by flow characteristics, not colour or quantity. Yet, the TBAs and lay women differed significantly from the SBAs in beliefs about normalcy of blood loss, causal role of the retained placenta and malevolent spirits, and care practices critical to survival. Cultural domain analysis captures variation in theories with specificity and representativeness necessary to inform community health intervention

Type, Content, and Source of Social Support Perceived by Women during Pregnancy: Evidence from Matlab, Bangladesh

Specific and contextualized data on social support during distinct health events are needed to improve social support interventions. This study identified the type, content, and source of social support perceived by women during pregnancy. In-depth interviews with 25 women, aged 18-49 years, living in Matlab, Bangladesh, were conducted. The findings demonstrated that women perceived, the receipt of eight distinct types of support. The four most frequently-mentioned types included: practical help with routine activities, information/advice, emotional support and assurance, as well as the provision of resources and material goods. Sources varied by type of support and most frequently included-\u2014mothers, mothers-in-law, sistersin-law, and husbands. Examples depicting the content of each type of support revealed culturally-specific issues that can inform community-based social support interventions

Ingroup friendship and political mobilization among the disadvantaged

This study investigated the effects of ingroup contact in a large, national sample of Māori (a disadvantaged ethnic group; N = 940) on political attitudes relevant to decreasing ethnic inequality in New Zealand. We tested the role of two mediating mechanisms – ethnic identification and system justification – in explaining the effects of ingroup contact on the dependent variables. Time spent with ingroup friends predicted increased support for the Māori Party and support for symbolic and resource-specific reparative policies benefiting Māori. These effects were partially mediated by increased ethnic identification. Although ingroup contact also reduced levels of system justification among Māori, its effects on policy attitudes and party preference were not mediated by system justification. This suggests that a key antecedent to system-challenging political attitudes is an increased sense of identification with a disadvantaged group arising, in part, from interactions with ingroup friends