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Epidemiological evidence and models have demonstrated that the current COVID-19 pandemic introduces a significant public risk to implementing large-scale community evacuations in response to disasters. While guidance documented in the US Environmental Protection Agency Protective Action Guidance (PAG) Manual is widely accepted as the standard basis for public and emergency worker protective actions for a radiological emergency, it is based primarily on assessing the risks associated with the radiological factors alone. However, as demonstrated in response to the nuclear incident in Fukushima, these events seldom occur in isolation from other risk-inducing events. Today, the COVID-19 pandemic represents a significant public health risk that must also be considered alongside the radiation risks in determining appropriate public and emergency worker protection action decisions. In particular, the significant public health risks associated with community transmission and mortality of COVID-19 challenge our most familiar and rehearsed radiological response strategies. The 1992 and 2017 US Environmental Protection Agency PAG manuals allow for considerations in protective action decision making. Much of the radiation emergency response community has been conditioned through decades of structured training and exercises to focus public protection considerations on specific guidelines referenced numerically in tables within the manual. Discussion regarding adjustment of specific PAG values is provided in the footnotes and bases portions of the PAG manual but is often not included in jurisdictional plans or routinely considered in exercises. However, when properly applied, the protective action guidance provides the necessary flexibility for decision-makers to account for additional public health risks or impediments, and jurisdictions can use this guidance to build a more effective response strategy. The authors have applied the full guidance and flexibility provided in the 2017 US Environmental Protection Agency PAG Manual to develop more specific guidance for their respective jurisdictions’ radiation emergency response plans and will outline a process for consideration of protective action decisions to maximize the protection of public health and safety.

The emerging promise of few-atom metal catalysts has driven the need for developing metal nanoclusters (NCs) with ultrasmall core size. However, the preparation of metal NCs with single-digit metallic atoms and atomic precision is a major challenge for materials chemists, particularly for Ag, where the structure of such NCs remains unknown. In this study, we developed a shape-controlled synthesis strategy based on an isomeric dithiol ligand to yield the smallest crystallized Ag NC to date: [Ag9(1,2-BDT)6]3– (1,2-BDT = 1,2-benzenedithiolate). The NC’s crystal structure reveals the self-assembly of two Ag square pyramids through preferential pyramidal vertex sharing of a single metallic Ag atom, while all other Ag atoms are incorporated in a motif with thiolate ligands, resulting in an elongated body-centered Ag9 skeleton. Steric hindrance and arrangement of the dithiolated ligands on the surface favor the formation of an anisotropic shape. Time-dependent density functional theory based calculations reproduce the experimental optical absorption features and identify the molecular orbitals responsible for the electronic transitions. Our findings will open new avenues for the design of novel single-digit metal NCs with directional self-assembled building blocks., An isomeric dithiol-based synthesis strategy is used to synthesize the smallest crystallized Ag nanocluster, [Ag9(1,2-BDT)6]3−. The single-digit cluster reveals novel bonding modes and building blocks, which include the self-assembly of two Ag square pyramids sharing a common vertex and six bidentate thiolate motifs.

Rapid detection of SARS-CoV-2 RNA is critical for reducing the global transmission of COVID-19. Here, we report a simple and versatile assay for detection of SARS-CoV-2 RNA based on aligner-mediated cleavage-based strand displacement amplification (AMC-SDA). The entire amplification procedure takes less than 25 min without professional instruments or requirement of specific target sequences and can reach a limit of detection of attomolar RNA concentration. Using pseudovirus as mimicry of clinical SARS-CoV-2 positive samples, we achieved a diagnostic accuracy of 100% in 10 simulated samples (five positive and five negative). We anticipate that our method will provide a universal platform for rapid and accurate detection of emerging infectious diseases.

Rhodium-alkene complexes of the pincer ligand κ3-C5H3N-2,6-(OPiPr2)2 (PONOP-iPr) have been prepared and structurally characterized: [Rh(PONOP-iPr)(η2-alkene)][BArF4] [alkene = cyclooctadiene (COD), norbornadiene (NBD), ethene; ArF = 3,5-(CF3)2C6H3]. Only one of these, alkene = COD, undergoes a reaction with H2 (1 bar), to form [Rh(PONOP-iPr)(η2-COE)][BArF4] (COE = cyclooctene), while the others show no significant reactivity. This COE complex does not undergo further hydrogenation. This difference in reactivity between COD and the other alkenes is proposed to be due to intramolecular alkene-assisted reductive elimination in the COD complex, in which the η2-bound diene can engage in bonding with its additional alkene unit. H/D exchange experiments on the ethene complex show that reductive elimination from a reversibly formed alkyl hydride intermediate is likely rate-limiting and with a high barrier. The proposed final product of alkene hydrogenation would be the dihydrogen complex [Rh(PONOP-iPr)(η2-H2)][BArF4], which has been independently synthesized and undergoes exchange with free H2 on the NMR time scale, as well as with D2 to form free HD. When the H2 addition to [Rh(PONOP-iPr)(η2-ethene)][BArF4] is interrogated using pH2 at higher pressure (3 bar), this produces the dihydrogen complex as a transient product, for which enhancements in the 1H NMR signal for the bound H2 ligand, as well as that for free H2, are observed. This is a unique example of the partially negative line-shape effect, with the enhanced signals that are observed for the dihydrogen complex being explained by the exchange processes already noted., η2-Alkene complexes [Rh(PONOP-iPr)(η2-alkene)][BArF4] [alkene = cyclooctadiene (COD), norbornadiene (NBD), ethene] are reported, for which only the COD complex undergoes significant onward reaction with H2 to form a cyclooctene (COE) complex, the reactivity is which is suggested to be due to intramolecular alkene-assisted reductive elimination. The putative product of H2 addition, [Rh(PONOP-iPr)(η2-H2)][BArF4], is made by an alternative route. Remarkably, enhanced signals for this dihydrogen complex are observed when pH2 is added to [Rh(PONOP-iPr)(η2-ethene)][BArF4], a unique example of the partially negative line-shape effect.

FutureTox IV, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in November 2018. Building upon FutureTox I, II, and III, this conference focused on the latest science and technology for in vitro profiling and in silico modeling as it relates to predictive developmental and reproductive toxicity (DART). Publicly available high-throughput screening data sets are now available for broad in vitro profiling of bioactivities across large inventories of chemicals. Coupling this vast amount of mechanistic data with a deeper understanding of molecular embryology and post-natal development lays the groundwork for using new approach methodologies (NAMs) to evaluate chemical toxicity, drug efficacy, and safety assessment for embryo-fetal development. NAM is a term recently adopted in reference to any technology, methodology, approach, or combination thereof that can be used to provide information on chemical hazard and risk assessment to avoid the use of intact animals (U.S. Environmental Protection Agency [EPA], Strategic plan to promote the development and implementation of alternative test methods within the tsca program, 2018, https://www.epa.gov/sites/production/files/2018-06/documents/epa_alt_strat_plan_6-20-18_clean_final.pdf). There are challenges to implementing NAMs to evaluate chemicals for developmental toxicity compared with adult toxicity. This forum article reviews the 2018 workshop activities, highlighting challenges and opportunities for applying NAMs for adverse pregnancy outcomes (eg, preterm labor, malformations, low birth weight) as well as disorders manifesting postnatally (eg, neurodevelopmental impairment, breast cancer, cardiovascular disease, fertility). DART is an important concern for different regulatory statutes and test guidelines. Leveraging advancements in such approaches and the accompanying efficiencies to detecting potential hazards to human development are the unifying concepts toward implementing NAMs in DART testing. Although use of NAMs for higher level regulatory decision making is still on the horizon, the conference highlighted novel testing platforms and computational models that cover multiple levels of biological organization, with the unique temporal dynamics of embryonic development, and novel approaches for estimating toxicokinetic parameters essential in supporting in vitro to in vivo extrapolation.

The electronic excited states of the iron(II) complex [FeII(tpy)(pyz-NHC)]2+ [tpy = 2,2′:6′,2″-terpyridine; pyz-NHC = 1,1′-bis(2,6-diisopropylphenyl)pyrazinyldiimidazolium-2,2′-diylidene] and their relaxation pathways have been theoretically investigated. To this purpose, trajectory surface-hopping simulations within a linear vibronic coupling model including a 244-dimensional potential energy surface (PES) with 20 singlet and 20 triplet coupled states have been used. The simulations show that, after excitation to the lowest-energy absorption band of predominant metal-to-ligand charge-transfer character involving the tpy ligand, almost 80% of the population undergoes intersystem crossing to the triplet manifold in about 50 fs, while the remaining 20% decays through internal conversion to the electronic ground state in about 300 fs. The population transferred to the triplet states is found to deactivate into two different regions of the PESs, one where the static dipole moment is small and shows increased metal-centered character and another with a large static dipole moment, where the electron density is transferred from the tpy to pyz-NHC ligand. Coherent oscillations of 400 fs are observed between these two sets of triplet populations, until the mixture equilibrates to a ratio of 60:40. Finally, the importance of selecting suitable normal modes is highlighted—a choice that can be far from straightforward in transition-metal complexes with hundreds of degrees of freedom., Trajectory surface-hopping simulations with a linear vibronic coupling model reveal the competition of major intersystem crossing versus minor internal conversion dynamics in an iron(II) N-heterocyclic carbene dye. The triplet population bifurcates into two regions of the potential energy surfaces, characterized by small and large static dipole moments due to different electronic character and showing coherent oscillations of 400 fs until both triplet populations coexist in a mixture of 60:40.

Surface topography variations of liquid crystal networks in their functional coatings provide unique properties in these systems. Chiral-nematic polymer coatings self-organize in a fingerprint texture with the molecular helices parallel to the substrate with alternating domains of molecular units with parallel and perpendicular director orientation as controlled by the concentration of a reactive chiral additive. Driven by surface-tension differences and altered by anisotropic polymerization shrinkage, the coating may form hills and valleys hundreds of nanometers in size with different molecular alignment. The director orientation in the corrugations could be controlled by monomer diffusion during polymerization. Polymerization in the presence of a dichroic dye gives topographic elevations in which the molecules are oriented along the normal. Polymerization by means of a dichroic photoinitiator gives topographic elevations in which the molecules align parallel to the surface. By balancing the monomer diffusion and anisotropic polymerization shrinkage, relatively flat surfaces are also achieved. The different surfaces exhibit distinct topographical deformations when subjected to external stimuli, such as an AC electric field. This method can be universally extended to LC polymers with other alignment configurations.

Emergency risk communication is a crucial part responding to crises. Right now, vulnerable groups are experiencing disproportionately negative outcomes from communication missteps surrounding COVID‐19. In this commentary, we describe the missteps and outline strategies that response organizations can take to improve communication for vulnerable groups.

Well-defined Ga(III) sites on SiO2 are highly active, selective, and stable catalysts in the propane dehydrogenation (PDH) reaction. In this contribution, we evaluate the catalytic activity toward PDH of tricoordinated and tetracoordinated Ga(III) sites on SiO2 by means of first-principles calculations using realistic amorphous periodic SiO2 models. We evaluated the three reaction steps in PDH, namely, the C-H activation of propane to form propyl, the β-hydride (β-H) transfer to form propene and a gallium hydride, and the H-H coupling to release H2, regenerating the initial Ga-O bond and closing the catalytic cycle. Our work shows how Brønsted-Evans-Polanyi relationships are followed to a certain extent for these three reaction steps on Ga(III) sites on SiO2 and highlights the role of the strain of the reactive Ga-O pairs on such sites of realistic amorphous SiO2 models. It also shows how transition-state scaling holds very well for the β-H transfer step. While highly strained sites are very reactive sites for the initial C-H activation, they are more difficult to regenerate. The corresponding less strained sites are not reactive enough, pointing to the need for the right balance in strain to be an effective site for PDH. Overall, our work provides an understanding of the intrinsic activity of acidic Ga single sites toward the PDH reaction and paves the way toward the design and prediction of better single-site catalysts on SiO2 for the PDH reaction., Inorganic Chemistry, 60 (10), ISSN:0020-1669, ISSN:1520-510X

ACS applied materials & interfaces 13(44), 51962 - 51973 (2021). doi:10.1021/acsami.1c08034, Herein, we report nanosecond, single-pulse laser post-processing (PLPP) in a liquid flat jet with precise control of the applied laser intensity to tune structure, defect sites, and the oxygen evolution reaction (OER) activity of mesostructured Co$_3$O$_4$. High-resolution X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) are consistent with the formation of cobalt vacancies at tetrahedral sites and an increase in the lattice parameter of Co$_3$O$_4$ after the laser treatment. X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) further reveal increased disorder in the structure and a slight decrease in the average oxidation state of the cobalt oxide. Molecular dynamics simulation confirms the surface restructuring upon laser post-treatment on Co$_3$O$_4$. Importantly, the defect-induced PLPP was shown to lower the charge transfer resistance and boost the oxygen evolution activity of Co$_3$O$_4$. For the optimized sample, a 2-fold increment of current density at 1.7 V vs RHE is obtained and the overpotential at 10 mA/cm$^2$ decreases remarkably from 405 to 357 mV compared to pristine Co$_3$O$_4$. Post-mortem characterization reveals that the material retains its activity, morphology, and phase structure after a prolonged stability test., Published by Soc., Washington, DC

The properties of metal–organic frameworks (MOFs) based on triiron oxo-centered (Fe3O) metal nodes are often related to the efficiency of the removal of the solvent molecules and the counteranion chemisorbed on the Fe3O unit by postsynthetic thermal treatment. Temperature, time, and the reaction environment play a significant role in modifying key features of the materials, that is, the number of open metal sites and the reduction of Fe(III) centers to Fe(II). IR spectroscopy allows the inspection of these postsynthetic modifications by using carbon monoxide (CO) and nitric oxide (NO) as probe molecules. However, the reference data sets are based on spectra recorded for iron zeolites and oxides, whose structures are different from the Fe3O one. We used density functional theory to study how the adsorption enthalpy and the vibrational bands of CO and NO are modified upon dehydration and reduction of Fe3O metal nodes. We obtained a set of theoretical spectra that can model the modification observed in previously reported experimental spectra. Several CO and NO bands were previously assigned to heterogeneous Fe(II) and Fe(III) sites, suggesting a large defectivity of the materials. On the basis of the calculations, we propose an alternative assignment of these bands by considering only crystallographic iron sites. These findings affect the common description of Fe3O-based MOFs as highly defective materials. We expect these results to be of interest to the large community of scientists working on Fe(II)- and Fe(III)-based MOFs and related materials., Thermal treatment of triiron oxo-centered (Fe3O)-based metal−organic frameworks is a common postsynthetic method to determine the material performances in many applications: we used density functional theory methods to study how the efficacy of the treatment modifies the energetics and the vibrational bands of nitric oxide (NO) and carbon monoxide. The obtained data set is meant to be part of the characterization toolboxes aimed at the assessment of thermal treatment protocols.

Countries across the globe have mobilized their armed forces in response to the COVID‐19 pandemic. Current contributions of armed forces have resulted from an urgent need for additional personnel and resources, and were facilitated by a framing of the crisis in terms of war. These deployments were in the interest of armed forces and enabled them to improve their operational readiness, boost their societal standing and support societies with their expertise. Even though armed forces may provide crucial aid in times of need, it is important that civilian crisis organizations are not undermined, civilian control and civil rights are guaranteed, and the effects on other military operations are considered and discussed. This Forum contribution offers some reflections and recommendations.

There is an increasing awareness that the gut microbiome plays a critical role in human health and disease, but mechanistic insights are often lacking. In June 2018, the Health and Environmental Sciences Institute (HESI) held a workshop, “The Gut Microbiome: Markers of Human Health, Drug Efficacy and Xenobiotic Toxicity” (https://hesiglobal.org/event/the-gut-microbiome-workshop) to identify data gaps in determining how gut microbiome alterations may affect human health. Speakers and stakeholders from academia, government, and industry addressed multiple topics including the current science on the gut microbiome, endogenous and exogenous metabolites, biomarkers, and model systems. The workshop presentations and breakout group discussions formed the basis for identifying data gaps and research needs. Two critical issues that emerged were defining the microbial composition and function related to health and developing standards for models, methods and analysis in order to increase the ability to compare and replicate studies. A series of key recommendations were formulated to focus efforts to further understand host-microbiome interactions and the consequences of exposure to xenobiotics as well as identifying biomarkers of microbiome-associated disease and toxicity.

The biological application of photoactivatable ruthenium anticancer prodrugs is limited by the need to use poorly penetrating high-energy visible light for their activation. Upconverting nanoparticles (UCNPs), which produce high-energy light under near-infrared (NIR) excitation, can solve this issue, provided that they form stable, water (H2O)-dispersible nanoconjugates with the prodrug and that there is efficient energy transfer from the UCNP to the ruthenium complex. Herein, we report on the synthesis and photochemistry of the ruthenium(II) polypyridyl complex [Ru(bpy)2(3H)](PF6)2 ([1](PF6)2), where bpy = 2,2-bipyridine and 3H is a photocleavable bis(thioether) ligand modified with two phosphonate moieties. This ligand was coordinated to the ruthenium center through its thioether groups and could be dissociated under blue-light irradiation. Complex [1](PF6)2 was bound to the surface of NaYF4:Yb3+,Tm3+@NaYF4:Nd3+@NaYF4 core–shell–shell (CSS-)UCNPs through its bis(phosphonate) group, thereby creating a H2O-dispersible, thermally stable nanoconjugate (CSS-UCNP@[1]). Conjugation to the nanoparticle surface was found to be most efficient in neutral to slightly basic conditions, resulting in up to 2.4 × 103 RuII ions per UCNP. The incorporation of a neodymium-doped shell layer allowed for the generation of blue light using low-energy, deep-penetrating light (796 nm). This wavelength prevents the undesired heating seen with conventional UCNPs activated at 980 nm. Irradiation of CSS-UCNP@[1] with NIR light led to activation of the ruthenium complex [1](PF6)2. Although only one of the two thioether groups was dissociated under irradiation at 50 W·cm–2, we provide the first demonstration of the photoactivation of a ruthenium thioether complex using 796 nm irradiation of a H2O-dispersible nanoconjugate., In this work, a water-dispersible nanoconjugate was prepared that is composed of blue-light-emitting core−shell−shell upconverting nanoparticles (CSS-UCNP) surface-functionalized with a blue-light-sensitive ruthenium polypyridyl complex. The photoactivation of this system was studied under 450, 796, and 980 nm light irradiation. Photosubstitution of the bis(thioether)−bis(phosphonate) ligand connecting the ruthenium complex to the UCNP surface was possible using high-power 796 nm near-infrared light irradiation, which led to partial ruthenium release from the nanoparticle surface.

Biofilm formation is most commonly combatted with antibiotics or biocides. However, proven toxicity and increasing resistance of bacteria increase the need for alternative strategies to prevent adhesion of bacteria to surfaces. Chemical modification of the surfaces by tethering of functional polymer brushes or films provides a route toward antifouling coatings. Furthermore, nanorough or superhydrophobic surfaces can delay biofilm formation. Here we show that submicrometer-sized roughness can outweigh surface chemistry by testing the adhesion of E. coli to surfaces of different topography and wettability over long exposure times (>7 days). Gram-negative and positive bacterial strains are tested for comparison. We show that an irregular three-dimensional layer of silicone nanofilaments suppresses bacterial adhesion, both in the presence and absence of an air cushion. We hypothesize that a 3D topography can delay biofilm formation (i) if bacteria do not fit into the pores of the coating or (ii) if bending of the bacteria is required to adhere. Thus, such a 3D topography offers an underestimated possibility to design antibacterial surfaces that do not require biocides or antibiotics.

We describe the history and features of the Ladder of Life Detection, a tool intended to guide the design of investigations to detect microbial life within the practical constraints of robotic space missions. To build the Ladder, we have drawn from lessons learned from previous attempts at detecting life and derived criteria for a measurement (or suite of measurements) to constitute convincing evidence for indigenous life. We summarize features of life as we know it, how specific they are to life, and how they can be measured, and sort these features in a general sense based on their likelihood of indicating life. Because indigenous life is the hypothesis of last resort in interpreting life-detection measurements, we propose a small but expandable set of decision rules determining whether the abiotic hypothesis is disproved. In light of these rules, we evaluate past and upcoming attempts at life detection. The Ladder of Life Detection is not intended to endorse specific biosignatures or instruments for life-detection measurements, and is by no means a definitive, final product. It is intended as a starting point to stimulate discussion, debate, and further research on the characteristics of life, what constitutes a biosignature, and the means to measure them.

Background and Aims: Chronic perineal pain (CPP) is a poorly localized pain. Its etiology may be benign or malignant. The ganglion impar is a solitary retroperitoneal structure at sacrococcygeal junction. It provides the nociceptive and sympathetic supply to the perineal structures. CPP has been effectively managed by ganglion impar block. Here, we describe a case series of neurolytic ganglion impar block by transcoccygeal approach, analyzing its safety and efficacy. Material and Methods: In this study, five consecutive patients who were given ganglion impar block for CPP using a transcoccygeal approach were followed up for 2 months. The visual analog scale (VAS) score for pain at presentation, time required for the pain to reduce by 50% after the block, VAS during a 2-month follow-up, time required to perform the procedure, number of attempts, and any complications were noted. Results: All the five patients had an excellent pain relief. The mean duration for decrease in VAS by 50% was 14.8 ± 3.1 min. The mean duration to perform the procedure was 10.2 ± 1.5 min. There were no complications. All the patients had clinically significant pain relief with VAS score of 2 till 2-month follow-up. Conclusion: Transcoccygeal ganglion impar block may offer a safe and effective treatment option for CPP as compared to opioids. This approach for neurolysis of the ganglion impar may be recommended in view of the direct course, appreciable end point, and smaller volume of neurolytic requirement.

Venous air embolism can be a catastrophic iatrogenic complication during operative hysteroscopy and makes this simple surgical procedure very risky, especially with the lack of knowledge about its prevention, presentation, and immediate management. Three out of 13 hysteroscopic myoma resections at our center had venous gas embolism (VGE). The prevention, diagnosis, and management of VGE are described in this report of three cases.

Background: The aim of this randomized split-mouth double-blind study was to evaluate whether 4% articaine hydrochloride with 1:100,000 epinephrine administered as a single buccal infiltration in the maxillary posterior sextant can provide palatal anesthesia when compared with 2% lignocaine with 1:100,000 epinephrine during scaling and root planing and access flap surgery (AFS). Material and Methods: A total of 40 patients with chronic generalized periodontitis requiring periodontal therapy in the maxillary posterior sextants were recruited in this study. About 4% articaine and 2% lignocaine were administered as buccal infiltration in a split-mouth design randomly. The pain scores in the palatal aspect were recorded during scaling and root planing and open flap debridement using Heft-Parker visual analog scale. The onset of anesthesia was also recorded and compared. Results: The success rate for maxillary buccal infiltration to induce palatal anesthesia using articaine was 90% during scaling and root planing and 82.5% during AFS and for lignocaine solution was 20% and 15%, respectively. The difference between the two agents was statistically significant (P < 0.05). The onset of anesthesia between articaine and lignocaine was also found to be statistically significant (P < 0.05). Conclusion: In this study, we observed that the efficacy of 4% articaine was superior to 2% lignocaine to induce palatal anesthesia following maxillary buccal infiltration in maxillary posterior sextants.

Boin (2019) argues that in transboundary crisis management it is almost impossible to achieve centralization and coordination. This article identifies three principles through which actors in a transboundary crisis can balance centralization with autonomy while shaping coordination along the way. We reanalysed three transboundary cases: the Dutch military mission in Afghanistan, the downing of MH17 and hurricane Irma striking Sint‐Maarten. The principles we found are as follows: (a) reformulating key strategic priorities, (b) flexible adaptation of crisis management protocols and (c) the emergence of multifunctional units. With these three principles, we reflect on challenges in the Dutch crisis response to the corona outbreak and propose improvements for progressing current crisis management efforts.

Background and Aims: India is a vast country with variable, nonuniform healthcare practices. A laryngoscope is an important tool during general anesthesia and resuscitation. The study aimed to determine the current practices of laryngoscope decontamination in India. Material and Methods: An online survey was conducted amongst 100 anesthesiologists to determine the common methods of laryngoscope decontamination adopted in their settings. The survey was done over 6 months after validating the questionnaire. Results: A total of 73 responses were received out of 100. The result of the survey revealed that there is no uniform technique of laryngoscope decontamination. There is marked variability in techniques followed not only among different institutions, but also within the same institution. Conclusion: There are no fixed protocols adopted for laryngoscope decontamination. Thus, there is a need to develop definitive guidelines on this subject, which can be implemented in India.

Objective: The phenomenal popularity of social networking sites has been used globally by medical professionals to boost professional associations and scientific developments. They have tremendous potential to forge professional liaisons, generate employment,upgrading skills and publicizing scientific achievements. We highlight the role of social networking mediums in influencing teaching, training and research in anaesthesiology. Background: The growth of social networking sites have been prompted by the limitations of previous facilities in terms of ease of data and interface sharing and the amalgamation of audio visual aids on common platforms in the newer facilities. Review: Contemporary social networking sites like Facebook, Twitter, Tumblr,Linkedn etc and their respective features based on anaesthesiology training or practice have been discussed. A host of advantages which these sites confer are also discussed. Likewise the potential pitfalls and drawbacks of these facilities have also been addressed. Conclusion: Social networking sites have immense potential for development of training and research in Anaesthesiology. However responsible and cautious utilization is advocated.

Bone remodeling relies on the coordinated functioning of osteoblasts, bone-forming cells, and osteoclasts, bone-resorbing cells. The effects of specific chemical and physical bone features on the osteoclast adhesive apparatus, the sealing zone ring, and their relation to resorption functionality are still not well-understood. We designed and implemented a correlative imaging method that enables monitoring of the same area of bone surface by time-lapse light microscopy, electron microscopy, and atomic force microscopy before, during, and after exposure to osteoclasts. We show that sealing zone rings preferentially develop around surface protrusions, with lateral dimensions of several micrometers, and ∼1 μm height. Direct overlay of sealing zone rings onto resorption pits on the bone surface shows that the rings adapt to pit morphology. The correlative procedure presented here is noninvasive and performed under ambient conditions, without the need for sample labeling. It can potentially be applied to study various aspects of cell-matrix interactions.

The synthesis, photophysics, and photochemistry of a linked dyad ([Re]-[NiFe2]) containing an analogue ([NiFe2]) of the active site of [NiFe] hydrogenase, covalently bound to a Re-diimine photosensitizer ([Re]), are described. Following excitation, the mechanisms of electron transfer involving the [Re] and [NiFe2] centers and the resulting decomposition were investigated. Excitation of the [Re] center results in the population of a diimine-based metal-to-ligand charge transfer excited state. Reductive quenching by NEt3 produces the radically reduced form of [Re], [Re]− (kq = 1.4 ± 0.1 × 107 M–1 s–1). Once formed, [Re]− reduces the [NiFe2] center to [NiFe2]−, and this reduction was followed using time-resolved infrared spectroscopy. The concentration dependence of the electron transfer rate constants suggests that both inter- and intramolecular electron transfer pathways are involved, and the rate constants for these processes have been estimated (kinter = 5.9 ± 0.7 × 108 M–1 s–1, kintra = 1.5 ± 0.1 × 105 s–1). For the analogous bimolecular system, only intermolecular electron transfer could be observed (kinter = 3.8 ± 0.5 × 109 M–1 s–1). Fourier transform infrared spectroscopic studies confirms that decomposition of the dyad occurs upon prolonged photolysis, and this appears to be a major factor for the low activity of the system toward H2 production in acidic conditions., Excitation of the [Re] center in the linked-dyad complex ([Re]-[NiFe2]) populates the 3MLCT excited state, and reductive quenching by NEt3 produces [Re]−. [Re]− reduces the [NiFe2] center to [NiFe2]− via inter- and intramolecular electron transfer pathways (kinter = 5.9 ± 0.7 × 108 M−1 s−1, kintra = 1.5 ± 0.1 × 105 s−1). For the analogous bimolecular system, where only intermolecular electron transfer could be observed, kinter = 3.8 ± 0.5 × 109 M−1 s−1.

Health physics is a recognized safety function in the holistic context of the protection of workers, members of the public, and the environment against the hazardous effects of ionizing radiation, often generically designated as radiation protection. The role of the health physicist as protector dates back to the Manhattan Project. Nuclear security is the prevention and detection of, and response to, criminal or intentional unauthorized acts involving or directed at nuclear material, other radioactive material, associated facilities, or associated activities. Its importance has become more visible and pronounced in the post 9/11 environment, and it has a shared purpose with health physics in the context of protection of workers, members of the public, and the environment. However, the duties and responsibilities of the health physicist in the nuclear security domain are neither clearly defined nor recognized, while a fundamental understanding of nuclear phenomena in general, nuclear or other radioactive material specifically, and the potential hazards related to them is required for threat assessment, protection, and risk management. Furthermore, given the unique skills and attributes of professional health physicists, it is argued that the role of the health physicist should encompass all aspects of nuclear security, ranging from input in the development to implementation and execution of an efficient and effective nuclear security regime. As such, health physicists should transcend their current typical role as consultants in nuclear security issues and become fully integrated and recognized experts in the nuclear security domain and decision making process. Issues regarding the security clearances of health physics personnel and the possibility of insider threats must be addressed in the same manner as for other trusted individuals; however, the net gain from recognizing and integrating health physics expertise in all levels of a nuclear security regime far outweighs any negative aspects. In fact, it can be argued that health physics is essential in achieving an integrated approach toward nuclear safety, security, and safeguards.

Background & Aims: Acute postoperative pain is still a neglected and unresolved issue in day to day practice. Acute pain services were conceived three decades ago to form a dedicated team to monitor pain assessment and treatment as per laid down pain protocols and guidelines. The concept of acute pain service (APS) is slowly evolving in India. Materials and Methods: This nationwide questionnaire survey was conducted to identify the status of postoperative pain, the prevalent treatment practices, opioid policy and the prevalence of acute pain services in India. An electronic communication was sent to 4000 Indian Society of Anesthesiologists life members. Results: We received only 146 responses mainly from faculties/consultants from few corporate hospitals or medical colleges. About 68 APSs are functioning, however, 20 APS do not have any training programs and 34 have no written protocols. Anesthesiologists are involved in postoperative pain management only when epidural analgesia is employed; otherwise surgeons are custodians of pain in the ward. Conclusion : This survey found that majority of anesthesiologists are agreeable to forming an APS and ready to take the responsibility, however administrative issues seem to be a major barrier.

Merging two topical themes in main-group chemistry, namely, cooperative bimetallics and frustrated-Lewis-pair (FLP) activity, this Forum Article focuses on the cooperativity-induced outcomes observed when the tris(alkyl)gallium compound GaR3 (R = CH2SiMe3) is paired with the lithium amide LiTMP (TMP = 2,2,6,6-tetramethylpiperidide) or the sterically hindered N-heterocyclic carbene (NHC) 1,3-bis(tert-butyl)imidazol-2-ylidene (ItBu). When some previously published work are drawn together with new results, unique tandem reactivities are presented that are driven by the steric mismatch between the individual reagents of these multicomponent reagents. Thus, the LiTMP/GaR3 combination, which on its own fails to form a cocomplex, functions as a highly regioselective base (LiTMP)/trap (GaR3) partnership for the metalation of N-heterocycles such as diazines, 1,3-benzoazoles, and 2-picolines in a trans-metal-trapping (TMT) process that stabilizes the emerging sensitive carbanions. Taking advantage of related steric incompatibility, a novel monometallic FLP system pairing GaR3 with ItBu has been developed for the activation of carbonyl compounds (via C=O insertion) and other molecules with acidic hydrogen atoms such as phenol and phenylacetylene. Shedding new light on how these non-cocomplexing partnerships operate and showcasing the potential of gallium reagents to engage in metalation reactions or FLP activations, areas where the use of this group 13 metal is scant, this Forum Article aims to stimulate more interest and activity toward the advancement of organogallium chemistry., Steric mismatches between GaR3 and LiTMP or N-heterocyclic carbenes switch on cooperative effects that enable the activation of organic molecules via trans-metal-trapping and frustrated-Lewis-pair approaches, respectively.

Hepatocytes, the main epithelial cell type in the liver, perform most of the biochemical functions of the liver. Thus, maintenance of a primary hepatocyte phenotype is crucial for investigations of in vitro drug metabolism, toxicity, and development of bioartificial liver constructs. Here, we report the impact of topographic cues alone and in combination with soluble signals provided by encapsulated feeder cells on maintenance of the primary hepatocyte phenotype. Topographic features were 300 nm deep with pitches of either 400, 1400, or 4000 nm. Hepatocyte cell attachment, morphology and function were markedly better on 400 nm pitch patterns compared with larger scale topographies or planar substrates. Interestingly, topographic features having biomimetic size scale dramatically increased cell adhesion whether or not substrates had been precoated with collagen I. Albumin production in primary hepatocytes cultured on 400 nm pitch substrates without collagen I was maintained over 10 days and was considerably higher compared to albumin synthesis on collagen-coated flat substrates. In order to investigate the potential interaction of soluble cytoactive factors supplied by feeder cells with topographic cues in determining cell phenotype, bioactive heparin-containing hydrogel microstructures were molded (100 μm spacing, 100 μm width) over the surface of the topographically patterned substrates. These hydrogel microstructures either carried encapsulated fibroblasts or were free of cells. Hepatocytes cultured on nanopatterned substrates next to fibroblast carrying hydrogel microstructures were significantly more functional than hepatocytes cultured on nanopatterned surfaces without hydrogels or stromal cells significantly elevated albumin expression and cell junction formation compared to cells provided with topographic cues only. The simultaneous presentation of topographic biomechanical cues along with soluble signaling molecules provided by encapsulated fibroblasts cells resulted in optimal functionality of cultured hepatocytes. The provision of both topographic and soluble signaling cues could enhance our ability to create liver surrogates and inform the development of engineered liver constructs.

After a summary of the problem of coupling electron and proton transfer to proton pumping in cytochrome c oxidase, we present the results of our earlier and recent density functional theory calculations for the dinuclear Fe-a3–CuB reaction center in this enzyme. A specific catalytic reaction wheel diagram is constructed from the calculations, based on the structures and relative energies of the intermediate states of the reaction cycle. A larger family of tautomers/protonation states is generated compared to our earlier work, and a new lowest-energy pathway is proposed. The entire reaction cycle is calculated for the new smaller model (about 185–190 atoms), and two selected arcs of the wheel are chosen for calculations using a larger model (about 205 atoms). We compare the structural and redox energetics and protonation calculations with available experimental data. The reaction cycle map that we have built is positioned for further improvement and testing against experiment., From density functional theory calculations on the dinuclear Fe-a3−CuB complex (DNC) in a type B bacterial cytochrome c oxidase, we construct a catalytic reaction wheel diagram for the full redox, O2 binding, and proton-transfer cycle. A new low-energy pathway is found. Strong shifts in the dipole moment direction/magnitude over the cycle and associated energy differences indicate that the DNC plays a major role not only in the chemical reaction cycle but also in proton pumping.

Brush-shaped amphiphilic block copolymers were conjugated with a monoclonal antibody against CD105 (i.e., TRC105) and a macrocyclic chelator for (64)Cu-labeling to generate multifunctional theranostic unimolecular micelles. The backbone of the brush-shaped amphiphilic block copolymer was poly(2-hydroxyethyl methacrylate) (PHEMA) and the side chains were poly(L-lactide)-poly(ethylene glycol) (PLLA-PEG). The doxorubicin (DOX)-loaded unimolecular micelles showed a pH-dependent drug release profile and a uniform size distribution. A significantly higher cellular uptake of TRC105-conjugated micelles was observed in CD105-positive human umbilical vein endothelial cells (HUVEC) than nontargeted micelles due to CD105-mediated endocytosis. In contrast, similar and extremely low cellular uptake of both targeted and nontargeted micelles was observed in MCF-7 human breast cancer cells (CD105-negative). The difference between the in vivo tumor accumulation of (64)Cu-labeled TRC105-conjugated micelles and that of nontargeted micelles was studied in 4T1 murine breast tumor-bearing mice, by serial positron emission tomography (PET) imaging and validated by biodistribution studies. These multifunctional unimolecular micelles offer pH-responsive drug release, noninvasive PET imaging capability, together with both passive and active tumor-targeting abilities, thus making them a desirable nanoplatform for cancer theranostics.

The development and design of new ligand systems with special donor properties has been essential for crucial advances made in main-group-element and transition-metal chemistry over the years. This Forum Article focuses on metalated ylides as novel ligand systems. These anionic congeners of bisylides possess likewise two lone pairs of electrons at the central carbon atom and can thus function as X,L-type ligands with strong donor abilities. This article highlights recent efforts in the isolation and application of metalated ylides with a focus on work from this laboratory. We summarize structural and electronic properties and their use in organic synthesis as well as main-group-element and transition-metal chemistry., Metalated ylides are unique ligand systems exhibiting unusual bonding situations and strong donor abilities. Because of their two lone pairs of electrons at the ylidic carbon atom, they can function as σ- and π-donor ligands. These properties can be applied in main-group-element and transition-metal chemistry, such as for the stabilization of electron-deficient or cationic species.

Spontaneous cholelithiasis was found in a male African green monkey (Chlorocebus aethiops) at necropsy. Choleliths varied in size, shape and colour. Gallstones were analysed using accepted analytical methods. Results showed that the gallstones were composed of cholesterol and protein in varying proportions. Histologically, the gallbladder showed diffuse mild to moderate lymphocytic infiltration. The etiology of the cholelithiasis in the examined individual remains unknown.

Pharmacological advances in anesthesia in recent decades have resulted in safer practice and better outcomes. These advances include improvement in anesthesia drugs with regard to efficacy and safety profiles. Although neuromuscular blockers were first introduced over a half century ago, few new neuromuscular blockers and reversal agents have come to market and even fewer have remained as common clinically employed medications. In recent years, newer agents have been studied and are presented in this review. With regard to nondepolarizer neuromuscular blocker agents, the enantiomers Gantacurium and CW002, which are olefinic isoquinolinium diester fumarates, have shown potential for clinical application. Advantages include ultra rapid reversal of neuromuscular blockade via cysteine adduction and minimal systemic hemodynamic effects with administration.

This Forum Article focuses on recent advances in structural and spectroscopic studies of biosynthetic models of nitric oxide reductases (NORs). NORs are complex metalloenzymes found in the denitrification pathway of Earth’s nitrogen cycle where they catalyze the proton-dependent two-electron reduction of nitric oxide (NO) to nitrous oxide (N2O). While much progress has been made in biochemical and biophysical studies of native NORs and their variants, a clear mechanistic understanding of this important metalloenzyme related to its function is still elusive. We report herein UV–vis and nuclear resonance vibrational spectroscopy (NRVS) studies of mononitrosylated intermediates of the NOR reaction of a biosynthetic model. The ability to selectively substitute metals at either heme or nonheme metal sites allows the introduction of independent 57Fe probe atoms at either site, as well as allowing the preparation of analogues of stable reaction intermediates by replacing either metal with a redox inactive metal. Together with previous structural and spectroscopic results, we summarize insights gained from studying these biosynthetic models toward understanding structural features responsible for the NOR activity and its mechanism. The outlook on NOR modeling is also discussed, with an emphasis on the design of models capable of catalytic turnovers designed based on close mimics of the secondary coordination sphere of native NORs., New insights into nitric oxide reductases (NORs) are obtained. Using nuclear resonance vibrational spectroscopy, we probe both iron atoms in mononitrosylated intermediates of the NOR reaction in a biosynthetic protein model that reveal new insights into the structural and electronic features responsible for the NOR activity and its likely mechanism.

The redox series [Irn(NHx)(PNP)] (n = II–IV, x = 3–0; PNP = N(CHCHPtBu2)2) was examined with respect to electron, proton, and hydrogen atom transfer steps. The experimental and computational results suggest that the IrIII imido species [Ir(NH)(PNP)] is not stable but undergoes disproportionation to the respective IrII amido and IrIV nitrido species. N–H bond strengths are estimated upon reaction with hydrogen atom transfer reagents to rationalize this observation and are used to discuss the reactivity of these compounds toward E–H bond activation., A square-planar redox series [Irn(NHx)(PNP)] (n = II−IV, x = 3−0; PNP = N(CHCHPtBu2)2) was examined with experimental and computational methods. The results indicate a particularly weak N−H bond within the imido species. The reactivity is rationalized with the [Irn(NHx)(PNP)] electronic structures and discussed in the context of ammonia and C−H bond activation.

Curiosity has reached the base of Mount Sharp, its promised land, the land where I hope it will at last perform its promised key analyses. Until now, Curiosity has been primarily an engineering mission, demonstrating an amazing landing technique and showing it can drive around the planet. The analyses reported allow NASA to state that the mission has achieved its “primary goal” of determining that Mars was once habitable. However, the science output has been limited and scarce. For more than two years on the Red Planet, Curiosity has unaccountably deferred performing analyses that are most directly concerned with evidence for life: the liquid extraction assay for organic compounds and the high-resolution imaging of green spots or areas Curiosity has shown on many of the nearby rocks. Requesting extension of their mission, Curiosity scientists proposed continuing its present program. In reviewing this request, NASA's 2014 Planetary Mission Senior Review panel highlighted this paucity in the mission's scientific productivity in its report published September 3, 2014. This panel of nationally known planetary science experts found “problems with the proposal were sufficiently severe they need addressing at the earliest opportunity.” The panel criticized that “only eight drilling samples are planned to be taken during the two year extended mission, that the panel considered a poor science return for such a large investment.” Further, the report stated, “The proposal lacked specific scientific questions and testable hypotheses.” I believe these same comments apply to the two plus years of work already completed by Curiosity. NASA has repeatedly stated that Curiosity carries no life-detection capability. This seems a very curious omission to me in that NASA has continuously stated that one of its prime objectives is to determine whether Mars had or has life. Prior to the launch of Viking, the agency stated that the search for life on Mars might be the greatest experiment in the history of science. Yet, despite the positive results from the Viking Labeled Release (LR) life-detection experiment in 1976, no life-detection experiment has ever since been sent to Mars. The claim that the Viking LR detected life, made by me and my Viking Co-Experimenter, Dr. Patricia A. Straat, remains disputed. Its results should certainly have been immediately queried by subsequent Mars probes. Even were the strong LR responses caused by chemistry, not life, they are an extraordinary finding that demands further investigation. Unfortunately, there was no clamor from the scientific community, and this omission will continue on the new Mars lander, tenuously planned for 2020. Following NASA's no-life-detection statement about Curiosity, I published an article (“Stealth Life Detection Instruments Aboard Curiosity,” Proc. SPIE 8521, Instruments, Methods, and Missions for Astrobiology XV, 852102, October 15, 2012, doi:10.1117/12.928032) addressing those Curiosity experiments I thought could confirm that the Viking LR experiment did detect life. Those experiments are the liquid extraction assay for complex organics (essential to support the claim for life) and use of the Mars Hand Lens Imager high-resolution camera for up-close inspection of some of the green spots shown on rocks in many of the large-scale images downloaded from Curiosity. The Mars Hand Lens Imager has a resolution of a fraction of the diameter of a human hair and therefore might reveal morphology indicative of biology. I made two predictions, as follows: (1) Curiosity would detect complex organic compounds and (2) Curiosity would confirm the presence of current liquid water (which it has since done). Neither the article nor my direct appeals to Curiosity scientists drew any comment or action on the organic and imaging issues. Thinking that these experiments might have been run, but not yet reported, I submitted an FOIA to NASA requesting them. The response came January 14, 2014, stating, For part one of your request, I could not locate any responsive Government records. Please be advised that the liquid extraction protocol of SAM has not yet been used on Mars. The methods that will be used for this liquid extraction are fully described in the attached open literature. For part two of your request, please be advised that all of the raw MAHLI images are released to the public on the JPL web site, and was signed by the Freedom of Information Act Public Liaison Officer, Records Manager. Scrutiny of published images by colleagues and myself has found no close-ups of the green spots on the rocks capable of showing possible biological patterns. The vitality (pun intended) of the Viking LR remains. No experiments are yet planned to test it. The statement at the Viking exhibit in the Smithsonian also remains: “Biological experiments on the Viking Landers did not detect signs of life.” To say there were no signs of life is woefully incorrect. Basically, there are three types of evidence: consistent, definitive, and compelling, in increasing order of certainty. Not only are the data from the Viking LR consistent with life, nothing we have learned about Mars is inconsistent with life. Terrestrial microorganisms have been grown under conditions as severe as on Mars, even surviving in naked space on the exterior of the International Space Station. Laboratory simulations have produced evidence that terrestrial ejecta produced by meteoric impact could arrive on Mars and deposit an infectious load of microorganisms. Indeed, it would now be surprising if life were not on Mars. As to being definitive, the strong Viking LR positive and control results would certainly be definitive on Earth. Such evidence, even minus any controls, was deemed compelling by public health authorities that relied on it daily for many decades in testing food and water. Yet scientific authorities question or reject the Viking LR claim to life. This doubt remains despite the failure of all published attempts to attribute the Viking LR results to chemistry, including a recent publication stating that galactic cosmic rays and solar energetic particles transform perchlorate in the martian soil into a compound that was responsible for those results. However, even this latest claim will be scientifically refuted in a forthcoming paper by Dr. Patricia A. Straat and me. Beginning with Viking and increasingly over the intervening years, some scientists knowledgeable in the field have expressed their opinions on the LR martian results in private to me or in public statements. Thinking that other scientists might be swayed in their opinions by knowing how these experts have evaluated the Viking LR data, a list of those respondents was developed. Depending on what they said, the scientists were listed in the category of “Has Detected Life” or “May Have Detected Life.” That list was then e-mailed to those named in it, and permission to include each one's name in a public article was requested. The updated list, with each name approved for such use, is shown in the accompanying Table 1. Table 1. Scientists Stating the Viking Labeled Release Experiment Detected or May Have Detected Life In light of the continuing controversy, perhaps a review of the Viking LR data by an independent panel, against the background of what we have learned since Viking about Mars as a habitat and about extremophiles on Earth, could resolve this major scientific issue. At a minimum, such a review would help NASA better formulate its plans for future Mars missions. In conclusion, I recommend the following actions in pursuing NASA's “Holy Grail” of life on Mars: (1) Implementation of Curiosity's liquid extraction protocol for organic compounds. (2) Taking of high-resolution close-ups of green spots on rocks by Curiosity's Mars Hand Lens Imager. (3) Review by an expert panel of the 1976 Viking LR data and other information pertinent to life on Mars.

Medical gases are nowadays being used for a number of diverse clinical applications and its piped delivery is a landmark achievement in the field of patient care. Patient safety is of paramount importance in the design, installation, commissioning, and operation of medical gas pipeline systems (MGPS). The system has to be operational round the clock, with practically zero downtime and its failure can be fatal if not restored at the earliest. There is a lack of awareness among the clinicians regarding the medico-legal aspect involved with the MGPS. It is a highly technical field; hence, an in-depth knowledge is a must to ensure safety with the system.

Institutions need to ignore some knowledge in order to function. This is “uncomfortable knowledge” because it undermines the ability of those institutions to pursue their goals (Rayner, 2012). We identify three bodies of knowledge that are relevant to understandings of the dual use threat posed by synthetic biology but are excluded from related policy discussions. We demonstrate how these “unknown knowns” constitute uncomfortable knowledge because they disrupt the simplified worldview that underpins contemporary discourse on the potential misuse of synthetic biology by malign actors. We describe how these inconvenient truths have been systematically ignored and argue that this is because they are perceived as a threat by organisations involved in the promotion of synthetic biology as well as by those involved in managing biosecurity risks. This has led to a situation where concerns about the biosecurity threat posed by synthetic biology are not only exaggerated, but are, more importantly, misplaced. This, in turn, means that related policies are misdirected and unlikely to have much impact. We focus on the dynamics of discussions about synthetic biology and dual use to demonstrate how the same “knowns” that are denied or dismissed as “unknown knowns” in certain circumstances are sometimes mobilised as “known knowns” by the same category of actors in a different context, when this serves to sustain the goals of the individuals and institutions involved. Based on our own experience, we argue that negotiating the dynamics of uncomfortable knowledge is a difficult, but necessary, component of meaningful transdisciplinary collaborations.

Background and Aims: Laparoscopic cholecystectomy is associated with a fairly high incidence of postoperative discomfort which is more of visceral origin than somatic. Studies have concluded that the instillation of local anesthetic with opioid around gall bladder bed provides more effective analgesia than either local anesthetic or opioid alone. Material and Methods: The study included 90 American Society of Anesthesiologists I-II patients of age 16-65 years scheduled for laparoscopic cholecystectomy under general anesthesia. The patients received the study drugs at the initiation of insufflation of CO 2 in the intraperitoneal space by the operating surgeon under laparoscopic camera guidance over the gallbladder bed. Patients in Group T received tramadol 2 mg/kg in 30 ml normal saline, in Group B received bupivacaine 30 ml of 0.125% and in Group BT received tramadol 2 mg/kg in 30 ml of 0.125% bupivacaine intraperitoneally. Postoperative pain assessment was done at different time intervals in the first 24 h using Visual Analog Scale of 0-10 (0 = No pain, 10 = Worst pain imagined). Time to first dose of rescue analgesic and total analgesics required in the first 24 h postoperatively were also recorded. The incidence of side effects during the postoperative period was recorded. Results: Reduction in postoperative pain was elicited, at 4 and 8 h postoperatively when Group BT (bupivacaine-tramadol group) was compared with Group T (tramadol group) or Group B (bupivacaine group) (P < 0.01). There was a significantly lower requirement of analgesics during first 24 h postoperatively in Group BT compared to Group B or T but no significant difference in the intake of analgesics was noted between Groups B Group T. Time to first dose of rescue analgesic was also significantly prolonged in Group BT compared to Group B or T. The incidence of nausea and vomiting was comparable in all the study groups. Conclusions: Intraperitoneal application of bupivacaine with tramadol was a more effective method for postoperative pain control after laparoscopic cholecystectomy compared to intraperitoneal bupivacaine or tramadol alone.

Background and Aims: Improvements in pain management techniques in the last decade have had a major impact on the practice of orthopedic surgeries, for example, total hip arthroplasty and total knee arthroplasty. Although there are a number of treatment options for postoperative pain, a gold standard has not been established. In our institution, both general anesthesia and regional anesthesia (RA), are being offered to the elderly orthopedic population but RA is not frequently accepted by elderly population. The objective of this study was to determine the frequency of various reasons for refusal of RA in elderly patients undergoing orthopedic surgeries. Material and Methods: A prospective study conducted over a period of 1 year, had 549 patients with ages above 60 years who underwent different types of elective orthopedic procedures 182 patients who refused RA were interviewed according to a structured questionnaire designed to assess the reasons of refusal. Statistical Analysis: Frequencies and percentages were computed for categorical variables. Chi-square test was applied to compare proportion difference of reasons for refusal of RA between gender, age groups, occupation, and previous history of anesthesia. Results: Most common reason for the refusal of RA was surgeon′s choice (38.5%), whereas 20.3% of the patients were unaware about the RA. There was a significant association between female gender and refusing RA due to backache (17.2%) and fear of being awake during the operation (24.1%) respectively. Conclusion: This survey showed that the main reasons among elderly female population were the fear of remaining awake and backache. However, overall it was the surgeon′s choice which made patients refuse RA, and the anesthesiologists were the main source of information.

Background and Aims: Peroral endoscopic myotomy (POEM) is a safe and minimally invasive modality regarded as the first-line management of all types of achalasia. POEM is performed under general anesthesia with endotracheal intubation using an orally inserted flexible fiberscope. The aim of this study is to describe the anesthetic management of POEM for achalasia. Material and Methods: A chart review of 21 patients who underwent POEM for achalasia at our center from March 2013 to June 2015 was performed. Results: In the 21 patients, the end-tidal carbon dioxide was elevated following esophageal carbon dioxide insufflation and required adjustments in ventilation. POEM was successfully completed, and the patients were extubated immediately afterward. Subcutaneous emphysema occurred in five patients. Complications such as mediastinitis, pleural effusion, pneumoperitoneum, and pneumomediastinum were managed conservatively. Esophageal perforation occurred in one patient and needed surgical intervention. Conclusion: For patients with achalasia, POEM offers the efficacy of surgery with the lower cost and morbidity of an endoscopic procedure. Prevention of aspiration and carbon dioxide insufflation-related complications are the two aspects that demand vigilance from the anesthesiologist.