核小体定位与RNA剪接

根据核小体定位序列和缺失序列的碱基分布特征,应用多样性增量二次判别方法(IDQD)构建模型对这两类序列进行了区分,受试者操作特性曲线下的面积达到了0.958．应用这一模型研究了核小体在人类基因组剪接位点(GT/AG)邻近序列中的分布方式,发现外显子所对应的DNA序列通常倾向参与核小体的形成,并且由它所转录的RNA统计上具有较强的刚性,而剪接位点及其邻近的内含子对应的DNA序列则避免参与核小体的形成,所转录的RNA统计上具有较强的柔性．进一步还发现,DNA序列的核小体定位/缺失和RNA的刚性/柔性具有统计相关性,为从机制上解释为何前体RNA剪接事件与DNA序列中的核小体定位信息有关提供了依据．     

Using porphyritic andesite as a new additive for improving hydrolysis and acidogenesis of solid organic wastes

The effects of porphyritic andesite on the hydrolysis and acidogenesis of solid organic wastes were investigated by batch and continuous experiments using a rotational drum fermentation system. The results of the batch experiment show that if porphyritic andesite (1%, 3%, and 5% reactants) is added initially, the pH level increases and hydrolysis and acidogenesis are accelerated. The highest surface based hydrolysis constant (26.4 × 10⁻³ kg m⁻² d⁻¹) and volatile solid degradation ratio (43.3%) were obtained at a 1% porphyritic andesite addition. In the continuous experiment, porphyritic andesite elevated the first order hydrolysis constant from 13.10 × 10⁻³ d⁻¹ to 18.82 × 10⁻³ d⁻¹. A particle mean diameter reduction rate of 33.05 μm/d and a volatile solid degradation rate of 3.53 g/L d⁻¹ were obtained under the hydraulic retention time of 4, 8, 12 and 16 d.     

Dosimetric impact of uncorrected systematic yaw rotation in VMAT for peripheral lung SABR

AimThis study aimed to evaluate the dosimetric impact of uncorrected yaw rotational error on both target coverage and OAR dose metrics in this patient population.BackgroundRotational set up errors can be difficult to correct in lung VMAT SABR treatments, and may lead to a change in planned dose distributions.Materials and methodsWe retrospectively applied systematic yaw rotational errors in 1° degree increments up to −5° and +5° degrees in 16 VMAT SABR plans. The impact on PTV and OARs (oesophagus, spinal canal, heart, airway, chest wall, brachial plexus, lung) was evaluated using a variety of dose metrics. Changes were assessed in relation to percentage deviation from approved planned dose at 0 degrees.ResultsTarget coverage was largely unaffected with the largest mean and maximum percentage difference being 1.4% and 6% respectively to PTV D98% at +5 degrees yaw.Impact on OARs was varied. Minimal impact was observed in oesophagus, spinal canal, chest wall or lung dose metrics. Larger variations were observed in the heart, airway and brachial plexus. The largest mean and maximum percentage differences being 20.77% and 311% respectively at −5 degrees yaw to airway D0.1cc, however, the clinical impact was negligible as these variations were observed in metrics with minimal initial doses.ConclusionsNo clinically unacceptable changes to dose metrics were observed in this patient cohort but large percentage deviations from approved dose metrics in OARs were noted. OARs with associated PRV structures appear more robust to uncorrected rotational error.     

Optimal group positioning after a predator attack: the influence of speed, sex, and satiation within mobile whirligig swarms

The position of animals within fish shoals, bird flocks, andinsect swarms is related to individual differences in hunger,body size, and defenses. These differences relate to the waythat animals balance multiple selection pressures includingfood-distribution and predator-attack patterns. However, therole of drafting/slipstreaming (taking advantage of the vorticesof those in front of you) and sex on the position of individualswithin a polarized group has not been well studied. For example,although hungry fish have been found to prefer positions towardthe front of a shoal on average, the mitigating factors of sex,recent predator exposure, and drafting have not been factoredinto this response. We conducted a controlled laboratory experimentwith individually marked whirligig beetles (Coleoptera: Gyrinidae)where sex and feeding level were controlled and the positionof beetles in a polarized group (in a flow tank) was analyzedat 2 different water speeds after exposure to a simulated predator.It was predicted that males and females would balance foragingand predator avoidance needs differently, as suggested by sexualsegregation theory and that males might be likely to occupyfront positions because of greater energetic needs. We foundthat in slow water males were more likely to occupy front positions,whereas in fast water females did, suggesting a different trade-offbetween the sexes in the need to forage versus save energy (draft).Additionally, we found that in slow water it was the hungrymales that came to the group's front, whereas hungry femaleswere more likely to move back. These are some of the first observationsof the positional complexity with which individuals in congregationsdisplay, and several adaptive and nonadaptive explanations forthe observed patterns are suggested.     

Normal coordinate analyses of 3,5-dichlorophenylcyanamide

The structure of 3,5-dichlorophenylcyanamide c-C₆H₃Cl₂–NHCN was investigated by DFT-B3LYP and ab initio MP2 calculations with the 6-311+G** basis set. The planar to perpendicular rotational barrier was calculated to be of about 5 kcal mol^–1 at both levels of calculation. The stability of the planar structure of the molecule was explained on the basis of conjugation effects between the cyanamide–NHCN moiety and the phenyl c-C₆H₅ ring in agreement with earlier NMR results. The CNC and the HNC bond angles were calculated to be about 120° especially by MP2 calculation, which is consistent with sp² (planar –NH–CN group) and not sp³ (pyramidal –NH–CN group) structure. The vibrational frequencies of the d₀, d₁ and d₃ species of 3,5-dichlorophenylcyanamide and the potential energy distributions among symmetry coordinates of the normal modes of the parent molecule were computed at the DFT-B3LYP level. The calculated infrared and Raman spectra of the molecule were plotted. Complete vibrational assignments were made on the basis of isotopic substitution and normal coordinate calculations.Figure Potential curves for the internal rotation in 3,5-dichlorophenylcyanamide as determined by DFT-B3LYP/6-311+G** (solid) and MP2/6-311+G** (dotted) calculations     

Rotating biological contactors: a review on main factors affecting performance

Rotating biological contactors (RBCs) constitute a very unique and superior alternative for biodegradable matter and nitrogen removal on account of their feasibility, simplicity of design and operation, short start-up, low land area requirement, low energy consumption, low operating and maintenance cost and treatment efficiency. The present review of RBCs focus on parameters that affect performance like rotational speed, organic and hydraulic loading rates, retention time, biofilm support media, staging, temperature, influent wastewater characteristics, biofilm characteristics, dissolved oxygen levels, effluent and solids recirculation, step-feeding and medium submergence. Some RBCs scale-up and design considerations, operational problems and comparison with other wastewater treatment systems are also reported.     

Ctdnep1 and Eps8L2 regulate dorsal actin cables for nuclear positioning during cell migration

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A proteomic approach to analysing spheroid formation of two human thyroid cell lines cultured on a random positioning machine

The human cell lines FTC-133 and CGTH W-1, both derived from patients with thyroid cancer, assemble to form different types of spheroids when cultured on a random positioning machine. In order to obtain a possible explanation for their distinguishable aggregation behaviour under equal culturing conditions, we evaluated a proteomic analysis emphasising cytoskeletal and membrane-associated proteins. For this analysis, we treated the cells by ultrasound, which freed up some of the proteins into the supernatant but left some attached to the cell fragments. Both types of proteins were further separated by free-flow IEF and SDS gel electrophoresis until their identity was determined by MS. The MS data revealed differences between the two cell lines with regard to various structural proteins such as vimentin, tubulins and actin. Interestingly, integrin α-5 chains, myosin-10 and filamin B were only found in FTC-133 cells, while collagen was only detected in CGTH W-1 cells. These analyses suggest that FTC-133 cells express surface proteins that bind fibronectin, strengthening the three-dimensional cell cohesion.     

Study of die back disease incidence of neem in Karnataka,India and PCR based identification of the isolates

A disease survey of die back of neem was done in different agroclimatic regions of Karnataka, India using Global Positioning System (GARMIN 12). Twigs of Azadirachta indica (Neem) infected with die back were collected from different regions of Karnataka, India and they were further analysed to determine the pathogen. Phomopsis azadirachtae the causal organism was isolated on malt extract agar from die back infected neem twigs. They were identified by conventional and molecular methods. Phomopsis genus specific primers (5.8S r-DNA) were then used for the detection of P. azadirachtae, the causative agent of die back of neem by polymerase chain reaction (PCR). Studies revealed the amplification of expected 141 bp DNA in P. azadirachtae isolated from the diseased trees of different regions of Karnataka indicating the causal organism of die back disease on neem. Studies revealed a very high incidence of die back in most of the places of Karnataka. This is the first report on disease incidence of die back of neem. Hand held GPS was used in the study which helps in continuous monitoring of the diseased trees.