Pharmacologic Analgesia for Cesarean Section: An Update in 2024.

PURPOSE OF THE REVIEW: With the increasing prevalence of cesarean section globally, the importance of perioperative analgesia for cesarean section is becoming increasingly evident. This article provides an overview and update on the current status of cesarean section worldwide and associated analgesic regimens. RECENT FINDINGS: Some recent studies unveiled potential association of neuraxial analgesia might be associated with children's autism, pharmacologic analgesia in obstetric will potentially gain some more attention. Various commonly used techniques and medications for analgesia in cesarean section are highlighted. While neuraxial administration of opioid remains the most classic method, the use of multimodal analgesia, particularly integration of nonsteroidal anti-inflammatory drugs, acetaminophen, peripheral nerve blocks has provided additional and better options for patients who are not suitable for intrathecal and neuraxial techniques and those experiencing severe pain postoperatively. Optimal pain management is crucial for achieving better clinical outcomes and optimal recovery, and with the continuous development of medications, more and better pharmacologic regimen will be available in the future.

Piezoelectric Response and Cycling Fatigue Resistance of Low-Temperature Sintered PZT-Based Ceramics.

The preparation of low-cost multilayer piezoelectric devices requires using cheap internal electrodes between the dielectric layers. A general strategy is to reduce the sintering temperature Ts of the ceramic layer by sintering aids which can form a liquid phase. Here, 0.2 wt% Li2CO3 was added as a sintering aid to tailor the sinterability and piezoelectricity of the commercial PZT ceramics. As verified from experiments, the piezoelectric ceramics could be densified at a sintering temperature above 940 °C, suitable for co-firing with the cheap internal electrode. The optimized sintering temperature of 980 °C can be confirmed for the 0.2 wt% Li2CO3-modified PZT ceramics due to its high piezoelectric coefficient d33 ~ 701 pC/N, planar coupling factor kp ~ 66.7%, and a low mechanical quality factor Qm ~ 71 with a transition temperature of Tc ~ 226 °C, presenting the characteristics of typical soft piezoelectric ceramics. Moreover, both the potential piezoelectric strain ~0.13% under 20 kV/cm and the good cycling fatigue characteristic (>104 cycles) of the studied piezo compositions indicates strong competitiveness in the field of multilayer piezoelectric devices.

An Anti-Aromatic Covalent Organic Framework Cathode with Dual-Redox Centers for Rechargeable Aqueous Zinc Batteries.

Covalent organic frameworks (COFs) are promising cathode candidates with high structural stability. However, they contain redox inactive linkages and experience low redox potential. Herein, a full anti-aromatic microporous COF cathode material of TAQ-BQ is designed for aqueous zinc batteries. The anti-aromatic conjugation effectively lowers the energy level of the lowest unoccupied molecular orbital as revealed by theoretical calculations, which corresponds to an elevated redox potential. Besides, the structure contains imino active sites at the linkages, in addition to carbonyl at the active parts. As a result, the TAQ-BQ cathode exhibits a voltage of 1.53 V/1.54 V and between 1.35 and 0.45 V in zinc cells. It delivers 208 mAh g-1 capacity at 0.1 A g-1 and maintains 136 mAh g-1 at 2 A g-1. Stable cycling is realized for 1000 cycles with 87% capacity retention. The co-de/insertion of Zn2+ and protons is identified for energy storage. Our work reveals the promises of COF cathode materials for aqueous zinc batteries.

The back-deposition of dissolved Mn2+ to MnO2 cathodes for stable cycling in aqueous zinc batteries.

The Mn2+ dissolution of MnO2 cathode materials causes rapid capacity decay in aqueous zinc batteries. We herein show that the dissolved Mn2+ can be deposited back to the cathode with the aid of a suitable conductive agent. The active material is thus retained for energy storage, and this MnO2/Mn2+ redox process also provides capacity. In the Mn2+ free ZnSO4 electrolyte, MnO2 delivers 325 mA h g-1 capacity at 0.1 A g-1, and 90.4% capacity retention is achieved after 3000 cycles at 5 A g-1. Our work demonstrates an effective strategy to realize stable cycling of MnO2 cathodes in aqueous zinc batteries without Mn2+ additives.

A high capacity small molecule quinone cathode for rechargeable aqueous zinc-organic batteries.

Rechargeable aqueous zinc-organic batteries are promising energy storage systems with low-cost aqueous electrolyte and zinc metal anode. The electrochemical properties can be systematically adjusted with molecular design on organic cathode materials. Herein, we use a symmetric small molecule quinone cathode, tetraamino-p-benzoquinone (TABQ), with desirable functional groups to protonate and accomplish dominated proton insertion from weakly acidic zinc electrolyte. The hydrogen bonding network formed with carbonyl and amino groups on the TABQ molecules allows facile proton conduction through the Grotthuss-type mechanism. It guarantees activation energies below 300 meV for charge transfer and proton diffusion. The TABQ cathode delivers a high capacity of 303 mAh g-1 at 0.1 A g-1 in a zinc-organic battery. With the increase of current density to 5 A g-1, 213 mAh g-1 capacity is still preserved with stable cycling for 1000 times. Our work proposes an effective approach towards high performance organic electrode materials.

Novel Ramie Fabric-Based Draping Evaporator for Tunable Water Supply and Highly Efficient Solar Desalination.

Interfacial solar-driven evaporation is a promising path to address the scarcity of freshwater. Lots of efforts have been made to develop highly efficient photothermal materials and optimize operational efficiency. However, the designed solar evaporator tends to directly contact with seawater, leading to inevitable parasitic heat loss and the total suppression of evaporation of the backside. Here, we show a novel draping fabric system by separating the evaporation interface from bulk water. The evaporation area was exposed to air with enhanced natural convection and double-side evaporation. The draping fabric was prepared by coating the mixture of carbon black (CB) and cross-linked sodium alginate (SA) on ramie fabric (CSRF). The draping CSRF realized an evaporation rate of 1.81 kg m-2 h-1 and efficiency of 96.6% under 1 sun illumination (1 kW m-2). In addition, by changing the yarn fineness of the fabric, a tunable water supply can be realized to optimize the energy distribution. This work provides a new strategy to design and optimize the solar evaporation system, exhibiting great potential in real-world applications.