A cross sectional study to evaluate indications and outcomes of caesarean section in a district hospital of West Bengal

Background: There is drastic rise in caesarean section (CS) rate worldwide in last decade as compared to optimal CS rate (10-15%) recommendation by WHO. This study was conducted to assess incidence and feto-maternal outcome in CS delivery.Methods: A cross-sectional study was conducted in pregnant women admitted over one year from September 2017- August 2018 in West Bengal. Demographic details and indication of CS were recorded along with documentation of feto-maternal outcomes. Statistical analysis was performed with help of Epi Info (TM) 7.2.2.2. Z-test and corrected Chi square (χ2) test. p<0.05 was considered to be statistically significant.Results: Out of total 10831 deliveries, 2914 (27%) women underwent CS. Demographic analysis shows maximum number of patients to be between 20-25years (51.7%), rural (58%), primigravida (51.3%), term pregnancy (87.7%). Non-progression of labour or NPL (45%) was most common indication of CS followed by previous CS (26.2%) and fetal distress (17.9%). Post CS wound infection was seen in 33 (1.1%) women. Two maternal deaths were recorded. Still born was documented in 0.8% while 6.8% fetus were referred to paediatric ICU.Conclusions: Rise in CS rates was mainly reported in 20-25 years age group, rural patients, in term pregnancy of primigravida patients. Most common indication for CS was NPL followed by previous CS and fetal distress. Mostly patients showed no complication in postpartum period. Only few patients had wound infection, hysterectomy and post-partum haemorrhage. More than 99% fetus survived without any complications.

Spatiotemporal characteristics in systems of diffusively coupled excitable slow-fast FitzHugh-Rinzel dynamical neurons

In this paper, we study an excitable, biophysical system that supports wave propagation of nerve impulses. We con- sider a slow-fast, FitzHugh-Rinzel neuron model where only the membrane voltage interacts diffusively, giving rise to the formation of spatiotemporal patterns. We focus on local, nonlinear excitations and diverse neural responses in an excitable 1- and 2-dimensional configuration of diffusively coupled FitzHugh-Rinzel neurons. The study of the emerg- ing spatiotemporal patterns is essential in understanding the working mechanism in different brain areas. We derive analytically the coefficients of the amplitude equations in the vicinity of Hopf bifurcations and characterize various patterns, including spirals exhibiting complex geometric substructures. Further, we derive analytically the condition for the development of antispirals in the neighborhood of the bifurcation point. The emergence of broken target waves can be observed to form spiral-like profiles. The spatial dynamics of the excitable system exhibits 2- and multi-arm spirals for small diffusive couplings. Our results reveal a multitude of neural excitabilities and possible conditions for the emergence of spiral-wave formation. Finally, we show that the coupled excitable systems with different firing characteristics, participate in a collective behavior that may contribute significantly to irregular neural dynamics

The generation of diverse traveling pulses and its solution scheme in an excitable slow-fast dynamics

In this paper, we report on the generation and propagation of traveling pulses in a homogeneous network of diffusively coupled, excitable, slow-fast dynamical neurons. The spatially extended system is modelled using the nearest neighbor coupling theory, in which the diffusion part measures the spatial distribution of the coupling topology. We derive analytically the conditions for traveling wave profiles that allow the construction of the shape of traveling nerve impulses. The analytical and numerical results are used to explore the nature of the propagating pulses. The symmetric or asymmetric nature of the traveling pulses is characterized and the wave velocity is derived as a function of system parameters. Moreover, we present our results for an extended excitable medium by considering a slow-fast biophysical model with a homogeneous, diffusive coupling that can exhibit various traveling pulses. The appearance of series of pulses is an interesting phenomenon from biophysical and dynamical perspective. Varying the perturbation and coupling parameters, we observe the propagation of activities with various amplitude modulations and transition phases of different wave profiles that affect the speed of the pulses in certain parameter regimes. We observe different types of traveling pulses, such as envelope solitons and multi-bump solutions and show how system parameters and the coupling play a major role in the formation of different traveling pulses. Finally, we obtain the conditions for stable and unstable plane waves

Dynamics of fractional order modified Morris-Lecar neural model

Most of the beautiful biological functions in neural systems are expected to happen considering the system with memory effect. Fractional differential equations are very useful to investigate long-range interacting systems or systems with memory effect. In this paper, a fractional order nonlinear three dimensional modified Morris-Lecar neural system (M-L system) has been studied. The fractional order M-L system is a generalization of the integer order M-L system. The paper presents an approximate analytical solution of the fractional order M-L system, using Homotopy Perturbation Method (HPM) and Variational Iteration Method (VIM). The fractional derivatives are described in the Caputo sense. We have used the above methods as they show very efficient result for very small time region. Solutions are obtained in the form of rapidly convergent infinite series and only a few iterations are needed to obtain the approximate solutions. Comparison of both HPM and VIM reveals that the two present methods of solution are elegant and powerful for solving the nonlinear fractional order biological as well as neural systems

No-till is more of sustaining the soil than a climate change mitigation option

No-till is often referred to as a climate change mitigation option, possibly with a stronger conviction, than as a practice to manage soil organic C (SOC) content. We conducted a global meta-analysis to evaluate the effect of no-till (NT) on SOC concentration (SOCc, g C kg−1 soil) and stock (SOCs, Mg C ha−1 land) across climate, soil texture, cropping systems, and no-till duration to appraise the priority-setting. Compared to conventional tillage, NT favoured a significant rise (ΔSOCc) of 38% in the 0–5 cm soil layer and a much lesser 6% increase in the 5–10 cm layer and no change beyond 10 cm. The temperate climate had nearly twice ΔSOCc in the 0–5 cm layer compared to other climates, while the tropical climate favoured sub-surface accumulation. Coarse- and medium-textured soils and the inclusion of legumes in crop rotation facilitated larger positive ΔSOCs under NT. The microbial biomass C was the most abundant C pool, with 61% and 23% increases under NT in 0–5 and 5–10 cm layers. A large ΔSOCc in aggregates also characterized the top 0–5 cm layer. The difference in SOCs was realized to a maximum 30 cm depth (5.4 Mg ha−1 or 14%) in favour of NT, although varying with the duration of its adoption. The contribution of NT in mitigating global anthropogenic greenhouse gas emissions is meagre, although it can substantially offset emissions from agriculture (17–58%). The benefit of NT in improving SOC is primarily restricted to the surface layer, which is potentially exposed, and therefore an increase could be short-lived. Nevertheless, a short-term gain in SOC is likely to enhance soil quality and crop productivity. Thus, NT may be promoted as a sustainable agricultural management practice rather than emphasizing its role as a potential climate change mitigation option

Use of Single-Metal Fragments for Cluster Building Synthesis, Structure, and Bonding of Heterometallaboranes

International audienceThe synergic property of the CO ligand, in general, can stabilize metal complexes at lower oxidation states. Utilizing this feature of the CO ligand, we have recently isolated and structurally characterized a highly fluxional molybdenum complex [{Cp*Mo(CO)}{μ-ηη-BH}] (2; Cp* = η-CMe) comprising the diborane(4) ligand. Compound 2 represents a rare class of bimetallic diborane(4) complex corresponding to a singly bridged C structure. In an attempt to isolate the tungsten analogue of 2, [{Cp*W(CO)}{μ-ηη-BH}], we have isolated a rare vertex-fused cluster, [(Cp*W)WBH] (5). Having a structural likeness with the dimolybdenum alkyne complex [{CpMo(CO)}CH], we have further explored the chemistry of 2 with CO gas that yielded a homoleptic trimolybdenum complex, [(Cp*Mo)(μ-H)(μ-H)(μ-CO)BH] (4). In an attempt to replace the 16-electron {Cp*MoH(CO)} moiety in 4 with isolobal fragment {W(CO)}, we treated the intermediate, obtained from the reaction of Cp*MoCl and LiBH, with the monometal carbonyl fragment {W(CO)·THF}. The reaction indeed yielded two bimetallic clusters, [(Cp*Mo)BHW(CO)] (7) and [(Cp*Mo)BHW(CO)] (8), that seem to have been generated by the replacement of one {BH} or {BH} vertex from [(Cp*Mo)BH], respectively. All of the compounds have been characterized by various spectroscopic analyses and single-crystal X-ray diffraction studies. Electron-counting rules and molecular orbital analyses provided further insight into the electronic structure of all of these molecules

Heterometallic boride clusters synthesis and characterization of butterfly and square pyramidal boride clusters

International audienceA number of heterometallic boride clusters have been synthesized and structurally characterized using various spectroscopic and crystallographic analyses. Thermolysis of [Ru-3(CO)(12)] with [Cp*WH3(B4H8)] (1) yielded [{Cp* W(CO)(2)}(2)(mu(4)-B){Ru(CO)(3)}(2)(mu-H)] (2), [{Cp*W(CO)(2)}(2) (mu(5) -B){Ru(CO)(3)}(2){Ru(CO)(2)}(mu-H)] (3), [{Cp*W(CO)(2)}(mu(5)-B){Ru(CO)(3)}(4)] (4) and a ditungstaborane cluster [(Cp*W)(2)B4H8Ru(CO)(3)] (5) (Cp*=eta(5)-C5Me5). Compound 2 contains 62 cluster valence-electrons, in which the boron atom occupies the semi-interstitial position of a M-4-butterfly core, composed of two tungsten and two ruthenium atoms. Compounds 3 and 4 can be described as hetero-metallic boride clusters that contain 74-cluster valence electrons (cve), in which the boron atom is at the basal position of the M-5-square pyramidal geometry. Cluster 5 is analogous to known [(Cp*W)(2)B5H9] where one of the BH vertices has been replaced by isolobal {Ru(CO)(3)} fragment. Computational studies with density functional theory (DFT) methods at the B3LYP level have been used to analyze the bonding of the synthesized molecules. The optimized geometries and computed B-11 NMR chemical shifts satisfactorily corroborate with the experimental data. All the compounds have been characterized by mass spectrometry, IR, H-1, B-11 and C-13 NMR spectroscopy, and the structural architectures were unequivocally established by crystallographic analyses of clusters 2-5

Combined Experimental and Theoretical Investigations of Group 6 Dimetallaboranes [(Cp*M)₂B₄H₁₀] (M = Mo and W)

Thermolysis of mono metal carbonyl fragment, [M′(CO)₅·thf, M′ = Mo and W, thf = tetrahydrofuran] with an <i>in situ</i> generated intermediate, obtained from the reaction of [Cp*MCl₄] (M = Mo and W, Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl) with [LiBH₄·thf], yielded dimetallaboranes, <b>1</b> and <b>2</b>. Isolations of [{Cp*M­(CO)}₂B₄H₆] (M = Mo (<b>1</b>) and W­(<b>2</b>)) provide direct evidence for the existence of saturated molybdaborane and tungstaborane clusters, [(Cp*M)₂B₄H₁₀]. Our extensive theoretical studies together with the experimental observation suggests that the intermediate may be a saturated cluster [(Cp^#M)₂B₄H₁₀], not unsaturated [(Cp^#M)₂B₄H₈] (Cp^# = Cp or Cp*), which was proposed earlier by Fehlner. Furthermore, in order to concrete our findings, we isolated and structurally characterized analogous clusters [(Cp*Mo)₂(CO)­(μ-Cl)­B₃H₄W­(CO)₄] (<b>3</b>) and [(Cp*WCO)₂(μ-H)₂B₃H₃W­(CO)₄] (<b>4</b>). All the compounds have been characterized by solution-state ¹H, ¹¹B, IR, and ¹³C NMR spectroscopy, mass spectrometry, and the structural architectures of <b>1</b>, <b>3</b>, and <b>4</b> were unequivocally established by X-ray crystallographic analysis. The density functional theory calculations yielded geometries that are in close agreement with the observed structures. Both the Fenske–Hall and Kohn–Sham molecular orbital analyses showed an increased thermodynamic stability for [(Cp^#M)₂B₄H₁₀] compared to [(Cp^#M)₂B₄H₈]. Furthermore, large HOMO–LUMO gap and significant cross cluster M–M bonding have been observed for clusters <b>1</b>–<b>4</b>