National variation in prophylactic antibiotic use for elective primary total joint replacement.

Aims: Prophylactic antibiotic regimens for elective primary total hip and knee arthroplasty vary widely across hospitals and trusts in the UK. This study aimed to identify antibiotic prophylaxis regimens currently in use for elective primary arthroplasty across the UK, establish variations in antibiotic prophylaxis regimens and their impact on the risk of periprosthetic joint infection (PJI) in the first-year post-index procedure, and evaluate adherence to current international consensus guidance. Methods: The guidelines for the primary and alternative recommended prophylactic antibiotic regimens in clean orthopaedic surgery (primary arthroplasty) for 109 hospitals and trusts across the UK were sought by searching each trust and hospital's website (intranet webpages), and by using the MicroGuide app. The mean cost of each antibiotic regimen was calculated using price data from the British National Formulary (BNF). Regimens were then compared to the 2018 Philadelphia Consensus Guidance, to evaluate adherence to international guidance. Results: The primary choice and dosing of the prophylactic antimicrobial regimens varied widely. The two most used regimens were combined teicoplanin and gentamicin, and cefuroxime followed by two or three doses of cefuroxime eight-hourly, recommended by 24 centres (22.02%) each. The alternative choice and dosing of the prophylactic antimicrobial regimen also varied widely across the 83 centres with data available. Prophylaxis regimens across some centres fail to cover the likeliest causes of surgical site infection (SSI). Five centres (4.59%) recommend co-amoxiclav, which confers no Staphylococcus coverage, while 33 centres (30.28%) recommend cefuroxime, which confers no Enterococcus coverage. Limited adherence to 2018 Philadelphia Consensus Guidance was observed, with 67 centres (61.50%) not including a cephalosporin in their guidance. Conclusion: This analysis of guidance on antimicrobial prophylaxis in primary arthroplasty across 109 hospitals and trusts in the UK has identified widespread variation in primary and alternative antimicrobial regimens currently recommended.

Attosecond Imaging of Electronic Wave Packets.

An electronic wave packet has significant spatial evolution besides its temporal evolution, due to the delocalized nature of composing electronic states. The spatial evolution was not previously accessible to experimental investigations at the attosecond timescale. A phase-resolved two-electron-angular-streaking method is developed to image the shape of the hole density of an ultrafast spin-orbit wave packet in the krypton cation. Furthermore, the motion of an even faster wave packet in the xenon cation is captured for the first time: An electronic hole is refilled 1.2 fs after it is produced, and the hole filling is observed on the opposite side where the hole is born.

Carrier-Envelope Phase Controlling of Ion Momentum Distributions in Strong Field Double Ionization of Methyl Iodide.

In strong field ionization of methyl iodide initiated by elliptically polarized few-cycle pulses, a significant correlation was observed between the carrier-envelope phases (CEPs) of the laser and the preferred ejection direction of methyl cation arising from dissociative double ionization. This was attributed to the carrier-envelope phase dependent double ionization yields of methyl iodide. This observation provides a new way for monitoring the absolute CEPs of few-cycle pulses by observing the ion momentum distributions.

Child Abuse: Approach and Management.

Child maltreatment is a devastating type of adverse childhood experience that encompasses neglect and emotional, physical, and sexual abuse (including sex trafficking). Adverse childhood experiences are exposures to maltreatment or household dysfunction during crucial developmental periods that disrupt neurodevelopment and can result in lifelong physical and psychological harm, altering the child's behavior and disease risk into adulthood. Maltreatment can affect patients of any gender identity and from all racial and ethnic backgrounds, socioeconomic statuses, and community settings. Use of the validated five-item Pediatric Hurt-Insult-Threaten-Scream-Sex screening tool to identify victims of child abuse is recommended. All suspected cases of child abuse must be reported to Child Protective Services. A trauma-informed approach to care requires that team members be mindful of the potential for traumatic stress, recognize and appropriately respond to the symptoms and signs of trauma, and prevent retraumatization. Prevention through education and anticipatory guidance provided during routine well-child visits and community partnerships can foster awareness and resiliency in children. Although caring for victims of child maltreatment may be among the most challenging professional situations encountered by physicians, advocating for these endangered patients can save lives and help prevent revictimization and chronic sequelae associated with adverse childhood experiences.

All-Optical Three-Dimensional Electron Momentum Imaging.

We report a new implementation of three-dimensional (3D) momentum imaging for electrons, employing a two-dimensional (2D) imaging detector and a silicon photomultiplier tube (siPMT). To achieve the necessary time resolution for 3D electron imaging, a poly(p-phenylene)-dye-based fast scintillator (Exalite 404) was used in the imaging detector instead of conventional phosphors. The system demonstrated an electron time-of-flight resolution comparable with that of electrical MCP pick-off (tens of picoseconds), while achieving an unprecedented dead time reduction (∼0.48 ns) when detecting two electrons.

Developing a camera-based 3D momentum imaging system capable of 1 Mhits/s.

A camera-based three-dimensional (3D) imaging system with a superb time-of-flight (TOF) resolution and multi-hit capability was recently developed for electron/ion imaging [Lee et al. J. Chem. Phys. 141, 221101 (2014)]. In this work, we report further improvement of the event rate of the system by adopting an event-driven camera, Tpx3Cam, for detecting the 2D positions of electrons, while a high-speed digitizer provides highly accurate (∼30 ps) TOF information for each event at a rate approaching 1 Mhits/sec.

Direct in-situ single-shot measurements of the absolute carrier-envelope phases of ultrashort pulses.

Many important physical processes such as nonlinear optics and coherent control are highly sensitive to the absolute carrier-envelope phase (CEP) of driving ultrashort laser pulses. This makes the measurement of CEP immensely important in relevant fields. Even though relative CEPs can be measured with a few existing technologies, the estimate of the absolute CEP is not straightforward and always requires theoretical inputs. Here, we demonstrate a novel in-situ technique based on angular streaking that can achieve such a goal without complicated calibration procedures. Single-shot measurements of the absolute CEP have been achieved with an estimated precision of 0.19 radians.

Safety and Efficacy of AAV5 Vectors Expressing Human or Canine CNGB3 in CNGB3-Mutant Dogs.

Achromatopsia is an inherited retinal disorder of cone photoreceptors characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. Approximately 50% of cases are caused by mutations in the cone photoreceptor-specific cyclic nucleotide gated channel beta subunit (CNGB3) gene. Studies in CNGB3-mutant dogs showed that subretinal injection of an AAV vector expressing human CNGB3, which has 76% amino acid identity with canine CNGB3, driven by a 2.1 kb human red cone opsin promoter (PR2.1) and packaged in AAV5 capsids (AAV5-PR2.1-hCNGB3) rescued cone photoreceptor function, but at high doses was associated with an inflammatory response (focal chorioretinitis) consistent with immune-mediated toxicity. AAV vectors containing the PR2.1 promoter packaged in AAV5 capsids and expressing either the native canine CNGB3 (AAV5-PR2.1-cCNGB3) or the human CNGB3 (AAV5-PR2.1-hCNGB3) were evaluated at different dose levels in CNGB3-mutant dogs. The vector expressing canine CNGB3 achieved somewhat better rescue of cone function but unexpectedly was associated with a greater degree of retinal toxicity than the vector expressing human CNGB3. Very low-level T-cell immune responses to some AAV or CNGB3 peptides were observed in animals that received the higher vector dose. There was a more than twofold increase in serum neutralizing antibodies to AAV in one of three animals in the low-dose group and in two of three animals in the high-dose group. No serum anti-hCNGB3 antibodies were detected in any animal. The results of this study do not support the hypothesis that the focal chorioretinitis seen with high doses of AAV5-PR2.1-hCNGB3 in the initial studies was due to an immune response to human CNGB3.