•Strut-and-tie method (STM) proposed for estimating in-plane strength of CM wall.•Parametric non-linear FE analysis used to establish limiting strut capacity.•Proposed STM closely predicts shear ...strength of walls with and without openings.
Strut-and-tie analysis is popularly used for the design of shear critical structures and can be applicable for the analysis of confined masonry (CM) walls, which often behave as shear walls. Properties of ties in a strut-and-tie model of CM wall can be simply computed from the yield strength of longitudinal reinforcement whereas that of masonry compression strut may depend on various parameters such as its aspect ratio, the strength of masonry and concrete. A non-linear parametric analysis was performed on more than 200 finite element models to understand the behaviour of masonry strut and a stepwise methodology for the formulation of the strut-and-tie model was proposed for CM walls. The proposed strut-and-tie method was validated by various experimental studies available in the literature. The developed strut-and-tie models consistently provided good predictions for the in-plane capacity of CM walls with and without openings when compared to the experimental results.
Meiotic abnormalities lead to morphological and genetic variations which caused not only to evolution but also intraspecific reproductive barriers. During present study of detailed meiotic course in ...dicotyledonous plants sampled from Indian cold deserts, various meiotic abnormalities have been detected. For this, the plant materials fixed in Carnoy's fixative and studied detailed meiotic course by standard squash method in 1% acetocarmine.
Meiotic abnormalities have been presently detected in 71 species which include multiple associations in diploids (Achillea millefolium L.), multivalents and univalents in polyploids (4 species), cytomixis (40 species), chromosome stickiness (20 species), nonsynchronous disjunction of bivalents (32 species), interbivalent connections (15 species), synaptic mutants (2 species), syncyte meiocytes (2 species), abnormal spindles (7 species), and fusion of pollen grains (1 species), laggards and chromatin bridges, hypo-, hyperploid PMCs, monads, dyads, triads, tetrads with micronuclei and polyads.
Consequently, variable sized apparently fertile pollen grains and considerable amount of sterile pollen grains are resulted as end products which lead to different genetic constitution (aneuploids and polyploids) and curtailed sexual reproductive success in these species.
•Proposed a preliminary seismic assessment technique using structural score.•Scores provide quick quantification of the seismic vulnerability of RC buildings.•Basic score was determined for archetype ...buildings with no irregularity.•Modifiers to basic score were presented for most common vertical irregularities.
Seismic vulnerability assessment of existing RC frame buildings is important for evaluating their performance to future earthquakes and accordingly plan risk mitigation strategies. Preliminary assessment technique is commonly used to quickly assess the vulnerability based on a sidewalk survey of a building. Majority of existing techniques only provide qualitative results which generally lead to difficulty in classifying building as vulnerable or not. A preliminary assessment method based on HAZUS has been developed for RC frame buildings designed as per Indian standards considering seismicity, soil conditions, frame-type and irregularities as main variables. The proposed technique provides both qualitative and quantitative assessment in a more engineered way by assigning a structural score to a building, which essentially defines its probability of collapse. Nonlinear-static pushover analysis has been performed on certain archetype buildings using open source software (OpenSEES) to develop the structural score of a building. Most commonly observed irregularities such as open ground storey, severe vertical irregularity, short-column and plan irregularity are considered for evaluating the structural score. The proposed structural score helps in taking a step forward to quickly quantify the vulnerability of RC framed buildings in India.
We report the occurrence of cytomixis in wild populations of Himalayan poppy (
Meconopsis aculeata
Royle), which is considered to be an important and threatened medicinal plant growing in the high ...hills of the Himalayas. The impact of cytomixis on meiotic behaviour, reduced pollen viability and heterogeneous-sized pollen grains was also studied. Cytological studies in the seven wild populations from the high hills of Himachal Pradesh revealed that all the Himalayan populations exist uniformly at the tetraploid level (2n=56) on x=14. The phenomenon of chromatin transfer among the proximate pollen mother cells (PMCs) in six populations caused various meiotic abnormalities. Chromatin transfer also resulted in the formation of coenocytes, aneuploid, polyploid and anucleated PMCs. Among individuals that showed chromatin transfer, chromosome stickiness and interbivalent connections were frequently observed in some PMCs. The phenomenon of cytomixis in the species seems to be directly under genetic control; it affects the meiotic course considerably and results in reduced pollen viability.
Introduction
Large abdominal wall hernias often require techniques for wall expansion to improve surgical outcomes. The peritoneal flap hernioplasty (PF) is one such technique that utilizes the ...hernia sac to reconstruct the abdominal wall, however, with limited published data. It is a modification of the Rives-Stoppa mesh repair where a part of the bisected hernia sac is utilized to reconstruct the anterior fascia and the other part for the posterior fascia. We present a collated retrospective analysis of the outcomes from three centers performing PF with or without transverse abdominis release (TAR) in patients with complex ventral hernias.
Methods
The PF was performed in patients with incisional hernias, both midline and lateral. The primary outcome measured was hernia recurrence. The secondary outcomes were to evaluate pain, surgical site infection, seroma, hematoma, wound dehiscence, pseudo-recurrence, Clavien–Dindo score for complications, and the patient's reported quality of life. The quality of life was assessed by oral questionnaires in the follow-up period.
Results
We analyzed 63 patients (38 female, 25 male) with a mean width of hernia defect of 11 cm SD 4. Based on the European Hernia Society (EHS) classification 42 patients were W3 and 21 were W2 hernias. Fifty patients had a midline hernia, while the rest of the patients included transverse, subcostal, and rooftop incision hernias. The classical peritoneal flap procedure was done in 29 (46%) patients, while the peritoneal flap with TAR was done in 34 (54%) patients. Four patients had symptomatic seroma (6%), seven superficial surgical site infection (SSI) (11%), one deep SSI (1.5%), one skin necrosis (1.5%), and one anterior peritoneal flap necrosis (1.5%). No patient required postoperative ventilatory support. The mean pain score on day one was 3/10. There was no recurrence in the mean follow-up of 17 months (range 5 to 49 months). Overall, 58 of 63 (92%) patients reported being satisfied with their surgery.
Conclusion
In our multicentre study, we found the PF technique with or without TAR for midline and non-midline ventral hernia leads to satisfactory outcomes in terms of low recurrence, low rate of complications, and a good quality of life in the medium to long term. It appears to be a useful technique in the surgeon’s armamentarium to repair W2 and W3 hernias needing expansion of abdominal domain.
Introduction
Subcostal hernias are categorized as L1 based on the European Hernia Society (EHS) classification and frequently involve M1, M2, and L2 sites. These are common after hepatopancreatic and ...biliary surgeries. The literature on subcostal hernias mostly comprises of retrospective reviews of small heterogenous cohorts, unsurprisingly leading to no consensus or guidelines. Given the limited literature and lack of consensus or guidelines for dealing with these hernias, we planned for a Delphi consensus to aid in decision making to repair subcostal hernias.
Methods
We adopted a modified Delphi technique to establish consensus regarding the definition, characteristics, and surgical aspects of managing subcostal hernias (SCH). It was a four-phase Delphi study reflecting the widely accepted model, consisting of:
Creating a query.
Building an expert panel.
Executing the Delphi rounds.
Analysing, presenting, and reporting the Delphi results.
More than 70% of agreement was defined as a consensus statement.
Results
The 22 experts who agreed to participate in this Delphi process for Subcostal Hernias (SCH) comprised 7 UK surgeons, 6 mainland European surgeons, 4 Indians, 3 from the USA, and 2 from Southeast Asia. This Delphi study on subcostal hernias achieved consensus on the following areas-use of mesh in elective cases; the retromuscular position with strong discouragement for onlay mesh; use of macroporous medium-weight polypropylene mesh; use of the subcostal incision over midline incision if there is no previous midline incision; TAR over ACST; defect closure where MAS is used; transverse suturing over vertical suturing for closure of circular defects; and use of peritoneal flap when necessary.
Conclusion
This Delphi consensus defines subcostal hernias and gives insight into the consensus for incision, dissection plane, mesh placement, mesh type, and mesh fixation for these hernias.
Bladder discomfort related to intraoperative catheterization of urinary bladder is a distressing symptom and more so in patients awakening from anaesthesia. These symptoms are similar to symptoms of ...overactive bladder. Muscarinic receptor antagonists have been reported to be effective in the treatment of overactive bladder. This study was therefore undertaken to evaluate the efficacy of oxybutynin and tolterodine in preventing catheter related bladder discomfort.
Two hundred and thirty-four consecutive adult patients, ASA I and II, of either sex, undergoing elective percutaneous nephrolithotomy surgery requiring urinary bladder catheterization were randomized into three equal groups of 78 each. Group C (control) received placebo, Group O (oxybutynin) received oxybutynin 5 mg and Group T (tolterodine) received tolterodine 2 mg orally 1 h before surgery. After induction of anaesthesia patients were catheterized with a 16 Fr Foley’s catheter and the balloon was inflated with 10 ml distilled water. The bladder discomfort was assessed at 0, 1, 2 and 6 h after patient’s arrival in the post-anaesthesia care unit. Severity of bladder discomfort was graded as mild, moderate and severe.
Incidence of bladder discomfort observed in the control group was higher, i.e. 58% (45/78), compared with oxybutynin and tolterodine groups where it was 35% (28/78) and 33% (26/78), respectively (P<0.05). Significant reduction in the severity of bladder discomfort was also observed after oxybutynin and tolterodine therapy compared with control (P<0.05).
Pretreatment with either oxybutynin or tolterodine reduces the incidence and severity of catheter related bladder discomfort.
Liquid-cooled microchannel heat sinks are regarded as being amongst the most effective solutions for handling high levels of heat dissipation in space-constrained electronics. However, obstacles to ...their successful incorporation into products have included their high pumping requirements and the limits on available space which precludes the use of conventional pumps. Moreover, the transport characteristics of microchannels can be different from macroscale channels because of different scaling of various forces affecting flow and heat transfer. The inherent potential of microchannel heat sinks, coupled with the gaps in understanding of relevant transport phenomena and difficulties in implementation, have guided significant research efforts towards the investigation of flow and heat transfer in microchannels and the development of microscale pumping technologies and novel diagnostics. In this paper, the potential and capabilities of microchannel heat sinks and micropumps are discussed. Their working principle, the state of the art, and unresolved issues are reviewed. Novel approaches for flow field measurement and for integrated micropumping are presented. Future developments necessary for wider incorporation of microchannel heat sinks and integrated micropumps in practical cooling solutions are outlined
Research on graphene/nanostructure hybrid materials has been gaining momentum in recent years, with wide-ranging applications in gas sensing and detection. Specifically, noble metal decorated ...graphene-based novel structures were found to be extremely sensitive and selective owing to the synergistic effect of the compound configuration. In this article, recent developments in graphene/noble metal nanostructure hybrids and their promising potential in gas sensing applications has been highlighted. More significantly, an understanding of the electronic mechanism of gas sensing is presented with a specific emphasis on electron transfer and junctions effects at the graphene/nanostructure interfaces. Finally, the future research prospects of application of bi-metallic and tri-metallic nanostructure/graphene-based hybrids and the challenges in this new and rapidly growing domain are discussed.
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