Elaboration and test of a decision rule for the application of mepiquat chloride on cotton in Mali

Farmers often make complex management decisions during a cropping cycle. To design new cropping systems that go beyond standard setups and are better adapted to local constraints, agronomists must formalize these farmer's decisions into decision rules that can be tested and disseminated. In Mali, there has been a marked decrease in cotton productivity over the last 10 years, whereas the area planted with cotton has doubled. However, cropping recommendations remain almost the same throughout the country. Cotton researchers have been asked to put forward new technical proposals suited to a wider range of socio-economic and biophysical cropping conditions.

The aim of this study was to develop a methodology to build a decision rule (DR) to help Malian farmers in making decisions on the use of growth regulators in cotton fields.

In the first phase, a 2-year experiment was conducted in two experimental stations, under a wide range of cotton vegetative growth conditions, along with different stand densities and fertilization rates. Mepiquat chloride (MC) was applied to half of the plots, and its effects were then computed against selected vegetative growth indicators measured before the date of MC application. A DR was proposed on this basis. In the second phase, the DR was tested in a six-village experiment. MC was applied in plots on 15 farms in each village and its effects on yield were recorded.

The results showed that is possible to build a DR for MC application based on LAI or aerial biomass indicators. The usual indicators, such as the five-node length technique, were not found to be useful. The response of cotton plots to MC for a given level of vegetative growth remained scattered, as other factors probably interfered, such as the length of the rainy season. Testing the DR in farmers’ fields showed that it was useful in determining appropriate MC applications. The usefulness of the DR is discussed on the basis of its accuracy and on the complexity of the selected indicator.     

Public health. Building microbial forensics as a response to bioterrorism

Combating bioterrorism is a challenge to all of us. To be proactive, the U.S. Government has formalized the discipline of "microbial forensics" to deter and attribute perpetrators of such acts. This Policy Forum describes the foundations of the microbial forensics program: the creation of a national bioforensics laboratory, a partnership laboratory network, and a peer-consensus scientific working group and the promulgation of quality assurance guidelines.     

Negligible effect of ions on the hydrogen-bond structure in liquid water

The effects of ions on bulk properties of liquid water, such as viscosity, have suggested that ions alter water's hydrogen-bonding network. We measured the orientational correlation time of water molecules in Mg(ClO4)2, NaClO4, and Na2SO4 solutions by means of femtosecond pump-probe spectroscopy. The addition of ions had no influence on the rotational dynamics of water molecules outside the first solvation shells of the ions. This result shows that the presence of ions does not lead to an enhancement or a breakdown of the hydrogen-bond network in liquid water.     

Protein kinase G from pathogenic mycobacteria promotes survival within macrophages

Pathogenic mycobacteria resist lysosomal delivery after uptake into macrophages, allowing them to survive intracellularly. We found that the eukaryotic-like serine/threonine protein kinase G from pathogenic mycobacteria was secreted within macrophage phagosomes, inhibiting phagosome-lysosome fusion and mediating intracellular survival of mycobacteria. Inactivation of protein kinase G by gene disruption or chemical inhibition resulted in lysosomal localization and mycobacterial cell death in infected macrophages. Besides identifying a target for the control of mycobacterial infections, these findings suggest that pathogenic mycobacteria have evolved eukaryotic-like signal transduction mechanisms capable of modulating host cell trafficking pathways.     

The risk of rinderpest re-introduction in post-eradication era

In 2011, ten years after the last reported outbreak, the eradication of rinderpest was declared. However, as rinderpest virus stocks still exist, there remains a risk of rinderpest re-introduction.     

Bronchoalveolar lavage fluid in Standardbred racehorses: Influence of unilateral/bilateral profiles and cut-off values on lower airway disease diagnosis

The aim of this study was to determine whether the lung side being sampled would significantly influence bronchoalveolar lavage (BAL) cytological profiles and subsequent diagnosis in Standardbred racehorses. One hundred and thirty-eight French Trotters in active training and racing were included in a prospective observational study. BAL was performed using videoendoscopy in both right and left lungs during summer meetings in 2011 (64 horses) and 2012 (74 horses). Cytological data performed 24 h later from right and left lungs were compared and specifically used to classify horses as affected with exercise-induced pulmonary haemorrhage (EIPH), inflammatory airway disease (IAD), or were ‘controls’. For IAD, cytological definition was based on two different cut off values.Neutrophil percentages, haemosiderophage percentages and the haemosiderophage/macrophage (H/M) ratios were significantly higher in the right compared to the left lung. Measures of intra-class correlation coefficients revealed a fair agreement between left and right lungs for percentages of mast cells, eosinophils, and for the H/M ratio, and a moderate agreement for neutrophil percentages. Fair to moderate agreements were observed between left and right lungs for the diagnosis of IAD and/or EIPH based on kappa coefficients. When sampling one lung only, the risk of incorrectly classifying a horse as a ‘control’ increased with the use of the restraint cut-off values for IAD. As BAL from one lung is not representative of the other lung in the same horse, both lungs should be sampled for a better assessment of lung cellularity and for a precise diagnosis of lower airway diseases.     

Ultrasound‐guided proximal paravertebral anaesthesia in cattle

ObjectiveTo develop and evaluate a method for ultrasound-guidance in performing the proximal paravertebral block for flank anaesthesia in cattle through a cadaveric study, followed by clinical application.Study designprospective experimental cadaveric study and clinical series.AnimalsPreviously frozen lumbar sections of cows without known spinal abnormalities were used. The clinical case group comprised of ten animals for which a right flank laparotomy was indicated.MethodsTwenty cow cadavers were used to perform ultrasound-guided bilateral injections of 1.0 mL dye (1.0 mL 1% Toluidine Blue in 1% Borax) at the intervertebral foramen at the level of T13, L1 and L2 spinal nerves. Distance and depth of injection, staining of the dorsal and ventral nerve branches, and deviation from the target were evaluated. The investigator’s confidence as to visualisation and expected success at staining the nerve was assessed. Ten clinical cases received the ultrasound-guided proximal paravertebral anaesthesia. Analgesic success was evaluated using a 4-grade scoring system at 10 minutes after the injection and during surgery, respectively. Categorical variables were described using frequencies and proportions.ResultsBoth dorsal and ventral branches of the spinal nerves T13, L1 or L2 were at least partially stained in 41% of injections, while in 77% of injections one of the branches was stained. Five out of ten clinical cases had a satisfactory anaesthesia. There was no significant association between confidence at injection and either staining or analgesic success.ConclusionResults from the cadaveric and clinical study suggest no significant improvement using ultrasound guidance to perform proximal paravertebral block in cows compared to our previous clinical experience and to references in the literature using the blind method.Clinical relevanceFurther research should be conducted to improve the ultrasound-guided technique described in this study.