In vitro effects of metals and pesticides on dehydrogenase activity in microbial community of cowpea (Vigna unguiculata) rhizoplane

Effects of heavy metals and pesticides on cowpea (Vigna unquiculata) rhizoplane microbial community  were assessed in vitro via dehydrogenase activity. The microbial community was exposed to various concentrations of heavy metals and pesticides in a nutrient broth-glucose-2,3,5-triphenyl chloride (TTC) medium. At 0.2 mM, iron and cadmium stimulated the dehydrogenase activity of the microbialcommunity. For all the metal ions, there was progressive inhibition with each successive increase in the concentration of metal ion, reaching near 100% at 0.6, 0.8, 1.2, 0.12 and 12 mM for cobalt, cadmium,iron, mercury and nickel, respectively. Between 0.2 and 0.4 mM, zinc sharply inhibited dehydrogenase activity and at concentration above 0.4 mm, inhibition of dehydrogenase activity became lesspronounced. The order of toxicity is Hg2+ > Co2+ > Cd2+ > Zn2+ > Fe2+ > Ni2+. The herbicides Cotrazine (Atrazine 80W) and Northrin®10EC stimulated dehydrogenase activity of the microbial community at 0.2% and inhibited it at higher concentrations. The median inhibitory concentrations (IC50s) of Cotrazine(Atrazine 80W) and Northrin®10EC were 0.552 ± 0.028 and 0.593 ± 0.051%, respectively. The dehydrogenase activity varied significantly (p < 0.05) with the type and concentrations of metals orpesticides. The result indicates that the heavy metals and pesticides are potentially toxic to V. unquiculata root surface microorganisms. In soil, this toxicity may affect nitrogen fixation processes and by extrapolation affect crop yield

Neonates presenting with severe complications of frenotomy: a case series

<p>Abstract</p> <p>Introduction</p> <p>Tongue-tie or ankyloglossia is an anatomic variation in which the lingual frenulum is thick, short or tight. It may be asymptomatic, or present with complications like breast feeding difficulties or speech, dental and cosmetic problems. The treatment of this condition, where indicated, is frenotomy. This procedure usually has few or no complications. However, when it is done by untrained personnel, it may lead to life-threatening complications. This paper highlights complications that could arise from improper treatment of ankyloglossia.</p> <p>Case presentation</p> <p>Case 1 was a one-day-old male neonate, a Nigerian of Igbo ethnicity, who was admitted with bleeding from the mouth and passage of dark stools after clipping of the frenulum by a traditional birth attendant. He was severely pale and in hypovolemic shock, with a severed frenulum which was bleeding actively. His packed cell volume was 15%. He was resuscitated with intravenous fluids and a blood transfusion. The bleeding was controlled using an adrenaline pack. He also received antibiotics. He was discharged five days later.</p> <p>Case 2 was a three-day-old male neonate, a Nigerian of Ikwerre ethnicity, who was admitted with profuse bleeding from a soft tissue injury under the tongue, after clipping of the frenulum by a community health worker. He was severely pale and lethargic. He was resuscitated with intravenous fluids and a blood transfusion. The bleeding vessel was ligated with repair of the soft tissue. He also received antibiotics and was discharged home one week later.</p> <p>Conclusion</p> <p>Treatment of tongue-tie, a benign condition, when done by untrained personnel may result in life-threatening complications. Clinicians should pay more attention to parents' worries about this condition and give adequate counseling or refer them to trained personnel for surgical intervention where clinically indicated.</p

A Critical Review on the Structural Health Monitoring Methods of the Composite Wind Turbine Blades

With increasing turbine size, monitoring of blades becomes increasingly im-portant, in order to prevent catastrophic damages and unnecessary mainte-nance, minimize the downtime and labor cost and improving the safety is-sues and reliability. The present work provides a review and classification of various structural health monitoring (SHM) methods as strain measurement utilizing optical fiber sensors and Fiber Bragg Gratings (FBG’s), active/ pas-sive acoustic emission method, vibration‒based method, thermal imaging method and ultrasonic methods, based on the recent investigations and prom-ising novel techniques. Since accuracy, comprehensiveness and cost-effectiveness are the fundamental parameters in selecting the SHM method, a systematically summarized investigation encompassing methods capabilities/ limitations and sensors types, is needed. Furthermore, the damages which are included in the present work are fiber breakage, matrix cracking, delamina-tion, fiber debonding, crack opening at leading/ trailing edge and ice accre-tion. Taking into account the types of the sensors relevant to different SHM methods, the advantages/ capabilities and disadvantages/ limitations of repre-sented methods are nominated and analyzed

Sample Delivery Techniques for Serial Crystallography

In serial femtosecond crystallography (SFX), protein microcrystals and nanocrystals are introduced into the focus of an X-ray free electron laser (FEL) beam ideally one-by-one in a serial fashion. The high photon density in each pulse is the double-edged sword that necessitates the serial nature of the experiments. The high photon count focused spatially and temporally leads to a diffraction-before-destruction snapshot, but this single snapshot is not enough for a high-resolution three-dimensional structural reconstruction. To recover the structure, more snapshots are required to sample all of reciprocal space from randomly oriented crystal diffraction, and in practice, some redundancy is necessary in these measurements. This chapter explores the different sample delivery techniques developed over the years to help enable serial crystallography experiments