Wastewater: A Potential Bioenergy Resource

Wastewaters are a rich source of nutrients for microorganisms. However, if left unattended the biodegradation may lead to severe environmental hazards. The wastewaters can thus be utilized for the production of various value added products including bioenergy (H₂ and CH₄). A number of studies have reported utilization of various wastewaters for energy production. Depending on the nature of the wastewater, different reactor configurations, wastewater and inoculum pretreatments, co-substrate utilizations along with other process parameters have been studied for efficient product formation. Only a few studies have reported sequential utilization of wastewaters for H₂ and CH₄ production despite its huge potential for complete waste degradation.     

Ethylene and IAA interactions in the inhibition of photoperiodic flower induction of <Emphasis Type="Italic">Pharbitis nil</Emphasis>

It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis.     

INFOS: spectrum fitting software for NMR analysis

Software for fitting of NMR spectra in MATLAB is presented. Spectra are fitted in the frequency domain, using Fourier transformed lineshapes, which are derived using the experimental acquisition and processing parameters. This yields more accurate fits compared to common fitting methods that use Lorentzian or Gaussian functions. Furthermore, a very time-efficient algorithm for calculating and fitting spectra has been developed. The software also performs initial peak picking, followed by subsequent fitting and refinement of the peak list, by iteratively adding and removing peaks to improve the overall fit. Estimation of error on fitting parameters is performed using a Monte-Carlo approach. Many fitting options allow the software to be flexible enough for a wide array of applications, while still being straightforward to set up with minimal user input.     

NdhO,a Subunit of NADPH Dehydrogenase,Destabilizes Medium Size Complex of the Enzyme in Synechocystis sp. Strain PCC 6803

Two mutants that grew faster than the wild-type (WT) strain under high light conditions were isolated from Synechocystis sp. strain PCC 6803 transformed with a transposon-bearing library. Both mutants had a tag in ssl1690 encoding NdhO. Deletion of ndhO increased the activity of NADPH dehydrogenase (NDH-1)-dependent cyclic electron transport around photosystem I (NDH-CET), while overexpression decreased the activity. Although deletion and overexpression of ndhO did not have significant effects on the amount of other subunits such as NdhH, NdhI, NdhK, and NdhM in the cells, the amount of these subunits in the medium size NDH-1 (NDH-1M) complex was higher in the ndhO-deletion mutant and much lower in the overexpression strain than in the WT. NdhO strongly interacts with NdhI and NdhK but not with other subunits. NdhI interacts with NdhK and the interaction was blocked by NdhO. The blocking may destabilize the NDH-1M complex and repress the NDH-CET activity. When cells were transferred from growth light to high light, the amounts of NdhI and NdhK increased without significant change in the amount of NdhO, thus decreasing the relative amount of NdhO. This might have decreased the blocking, thereby stabilizing the NDH-1M complex and increasing the NDH-CET activity under high light conditions.     

Structure and growth pattern of the bizarre hemispheric prominence on the rostrum of the fossil beaked whale Globicetus hiberus (Mammalia,Cetacea, Ziphiidae)

The rostrum of most ziphiids (beaked whales) displays bizarre swollen regions, accompanied with extreme hypermineralisation and an alteration of the collagenous mesh of the bone. The functional significance of this specialization remains obscure. With the voluminous and dense hemispheric excrescence protruding from the premaxillae, the recently described fossil ziphiid Globicetus hiberus is the most spectacular case. This study describes the histological structure and interprets the growth pattern of this unique feature. Histologically, the prominence in Globicetus is made up of an atypical fibro‐lamellar complex displaying an irregular laminar organization and extreme compactness (osteosclerosis). Its development is suggested to have resulted from a protraction of periosteal accretion over the premaxillae, long after the end of somatic growth. Complex shifts in the geometry of this tissue are likely to have occurred during its accretion and no indication of Haversian remodeling could be found. X‐ray diffraction and Raman spectroscopy indicate that the bone matrix in the premaxillary prominence of Globicetus closely resembles that of the rostrum of the extant beaked whale Mesoplodon densirostris: apatite crystals are of common size and strongly oriented, but the collagenous meshwork within bone matrix seems to be extremely sparse. These morphological and structural data are discussed in the light of functional interpretations proposed for the highly unusual and diverse ziphiid rostrum. J. Morphol. 277:1292–1308, 2016. © 2016 Wiley Periodicals, Inc.     

Percutaneous closure of a patent foramen ovale after cryptogenic stroke

A patent foramen ovale is a common intracardiac finding that is located between the left and right atrium. It can cause right-to-left shunting and has a high prevalence in patients who suffer a cryptogenic stroke. Earlier trials did not show superiority of percutaneous patent foramen ovale closure with standard medical therapy over standard medical therapy alone in the treatment of cryptogenic stroke. Interestingly, several meta-analyses show positive results regarding closure, suggesting underpowering of the individual trials. Recently, two large prospective trials and one long-term follow-up study showed benefit of percutaneous closure over standard medical therapy in treatment of cryptogenic stroke. A larger right-to-left shunt or the presence of an atrial septal aneurysm were predictors for a recurrent event. Therefore, percutaneous patent foramen ovale closure after cryptogenic stroke should be recommended over antiplatelet therapy alone in patients younger than 55 years of age with a high-risk patent foramen ovale.