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In this article, we report the development of ruthenium-catalyzed hydrogenolysis of epoxides to selectively give the branched (Markovnikov) alcohol products. In contrast to previously reported catalysts, the use of Milstein’s PNN-pincer-ruthenium complex at room temperature allows the conversion of enantiomerically enriched epoxides to secondary alcohols without racemization of the product. The catalyst is effective for a range of aryl epoxides, alkyl epoxides, and glycidyl ethers and is the first homogeneous system to selectively promote hydrogenolysis of glycidol to 1,2-propanediol, without loss of enantiomeric purity. A detailed mechanistic study was conducted, including experimental observations of catalyst speciation under catalytically relevant conditions, comprehensive kinetic characterization of the catalytic reaction, and computational analysis via density functional theory. Heterolytic hydrogen cleavage is mediated by the ruthenium center and exogenous alkoxide base. Epoxide ring opening occurs through an opposite-side attack of the ruthenium hydride on the less-hindered epoxide carbon, giving the branched alcohol product selectively.

Massive bone destruction in a human right proximal femur is described and differentially discussed in this case study. The individual was an older adult female buried at the ancient Nubian site of Tombos (modern-day Sudan) dating to the early Napatan/Third Intermediate Period (c. 1069-750 BCE). The right femur displayed a pathologic fracture with extensive lytic destruction and resorption of the entire femoral neck, most of the femoral head, and trochanters. Macroscopic and radiographic analyses revealed cortical thinning of the proximal diaphysis with new bone formation enclosing the medullary cavity. The lesion is eccentrically located involving the anterior aspect of the neck. Numerous vascular channels are apparent in the underlying bone. Sclerotic bone marks the limit of the lesion, and osseous lucency is visible in the radiograph. The individual displayed no other lytic lesions; vertebral osteophytic growth, compression fractures, and Schmorl’s nodes were observed along with dental disease typical for older individuals. A traumatic etiology is eliminated due to the extensive osteolysis. Vascular, congenital, and developmental conditions are also not consistent with the observed changes. Expansive osteolytic lesions may have been caused by a cyst. Neoplastic tumors resulting in lytic lesions with a high risk of pathologic fracture are also consistent. There have been few reports of such extensive lytic lesions of the proximal femur in the paleopathological and clinical literature; this case adds an example of this underreported condition.

We have been treating children with Legg-Calvé-Perthes disease (LCPD) with a femoral varus osteotomy (PFVO) and weight relief till the disease evolves to the latter part of the stage of reconstitution (Stage IIIb). This entails weight relief for 18 to 24 months. We undertook this case-control study to test if a shorter period of weight relief would compromise the chance of retaining the spherical shape of the femoral head when the disease healed. Forty-one children diagnosed in the early stages of LCPD (Stages Ia, Ib, and IIa), were treated by PFVO and non–weight-bearing for a period of 6 months following surgery (6m group). Eighty-two children with LCPD matched for age, sex, and stage at surgery, who resumed weight-bearing only once they reached Stage IIIb, served as the control group (3b group). Both groups were followed up till the disease healed. The sphericity deviation score was calculated, and the height and width of the epiphysis were measured on the first radiograph designated as Stage IV. The median sphericity deviation score value at healing was 3 in the 3b group and 11 in the 6m group (P<0.001). The frequency of spherical heads was 76% in the 3b group and 49% in the 6m group (P<0.003). The Odds Ratio of the disease healing with an aspherical head in 6-month group was 3.05 (CI: 1.28 to 7.22) compared with the 3b group. The percentage increase in width of the femoral epiphysis at healing was greater in the 6 group (111.5±8.5% vs. 106.5±7.2%; P<0.001). The study confirms that containment by PFVO performed early in the course of LCPD combined with weight relief till the disease has evolved to Stage IIIb is likely to result in spherical hips in 75% of children. Reducing the period of weight relief to 6 months may yield significantly poorer results with only 49% spherical femoral heads.

A famous painting of the 19th century, by Ilia Repin, of a religious procession depicts the pageantry of the event but also draws the attention of the viewer to the exclusion of a disabled child from the festivities.

Study of disease-relevant immune cells, namely monocytes and macrophages, is limited based on availability of primary tissue, a limitation that can be remedied using human induced pluripotent stem cell (hiPSC) technology. Here, we present a protocol for differentiation of monocytes and macrophages from hiPSCs. We describe steps for hiPSC maintenance, mesoderm lineage induction, hematopoietic progenitor cells (HPCs) commitment and expansion, and myeloid lineage induction. We then detail procedures for monocyte formation and functional macrophage formation and polarization.

The main communicative purpose of Letters of Recommendation (LORs) is to share the writer’s evaluation of the candidate. Every kind of evaluation draws distinctively on resources of grammar. To this end, Martin and White’s (2005) Appraisal System was adopted to examine the mechanisms through which some lecturers of a Ghanaian university express their evaluation in 35 purposively sampled letters. The study concludes that evaluation plays a crucial role in the construal of ideology, voice and stance in the LORs genre, and that the dominance of judgement is a proof of the communicative purpose of the LOR genre.

William Collins and Pieter Bruegel the Elder in their respective paintings, “Happy as a King” and “Children’s Games” show children playing outdoors. The types of injuries these children could sustain in the 16th and 19th centuries are contrasted with sports related pediatric fractures in the present day.

AimsThe study was undertaken to compare the efficacy of Woodcast splints and plaster-of-Paris casts in maintaining correction following sequential manipulation of idiopathic clubfeet.MethodsIn this randomized prospective trial, 23 idiopathic clubfeet were immobilized with plaster-of-Paris casts and 23 clubfeet were immobilized with a splint made of Woodcast that encircled only two-thirds the circumference of the limb. The number of casts or splints needed to obtain full correction, the frequency of cast or splint-related complications, and the time taken for application and removal of the casts and splints were compared.ResultsThe mean number of casts required to obtain full correction of the deformity (Pirani Score 0) was 4.35 (95% confidence interval (CI) 3.74 to 4.95) when plaster-of-Paris was used and 4.87 (95% CI 4.33 to 5.41) when the Woodcast splint was used (p = 0.190). The time required for application and removal of the Woodcast splint were significantly less than that required for application and removal of plaster-of-Paris casts (p < 0.001). Woodcast splint-related complications were not more frequent than plaster-of-Paris cast related complications.ConclusionThough Woodcast splints covering two-thirds of the circumference of the lower limbs of infants were effective in maintaining the correction of clubfoot deformity during serial manipulation and casting treatment, the superiority of Woodcasts over plaster-of-Paris could not be established.Cite this article: Bone Joint J2020;102-B(10):1399–1404.

Stanislaw Wyspianski, a multifaceted Polish artist painted “A Girl with a Red Hat”, which portrays a young girl with an obviously deformed right upper limb. The pattern of deformities is suggestive of either athetoid hemiplegic cerebral palsy or Erb’s palsy.

In Pieter Bruegel’s painting, “The Seven Acts of Charity” he portrays 2 subjects with flexed knees. One of them cannot walk while the other can walk but does so with excessive energy expenditure.

Pierre Auguste Cot’s painting, “Mireille giving alms at the door of Saint-Trophime,” depicts a wealthy lady giving alms to a crippled beggar boy. The beautiful painting portrays the striking contrast between the rich and the poor. The painting also draws attention to the crude crutch the boy was using. This type of crutch was used over the centuries; improvements in the design of the axillary crutch occurred only in the 20th century.

Raja Ravi Varma’s painting “There Comes Papa” depicts his daughter carrying her son astride her hip. The positive implication of the posture of the hips of the child while being carried in this manner on acetabular development is discussed.

The Sad Inheritance painted by Sorolla depict children with polio. The clarity of the painting enables the viewer to identify gait abnormalities due to muscle paralysis.

The COVID‐19 pandemic continues to pose a substantial threat to human lives and is likely to do so for years to come. Despite the availability of vaccines, searching for efficient small‐molecule drugs that are widely available, including in low‐ and middle‐income countries, is an ongoing challenge. In this work, we report the results of an open science community effort, the “Billion molecules against COVID‐19 challenge”, to identify small‐molecule inhibitors against SARS‐CoV‐2 or relevant human receptors. Participating teams used a wide variety of computational methods to screen a minimum of 1 billion virtual molecules against 6 protein targets. Overall, 31 teams participated, and they suggested a total of 639,024 molecules, which were subsequently ranked to find ‘consensus compounds’. The organizing team coordinated with various contract research organizations (CROs) and collaborating institutions to synthesize and test 878 compounds for biological activity against proteases (Nsp5, Nsp3, TMPRSS2), nucleocapsid N, RdRP (only the Nsp12 domain), and (alpha) spike protein S. Overall, 27 compounds with weak inhibition/binding were experimentally identified by binding‐, cleavage‐, and/or viral suppression assays and are presented here. Open science approaches such as the one presented here contribute to the knowledge base of future drug discovery efforts in finding better SARS‐CoV‐2 treatments.

The work of art by Monet shows a young child sitting with the toes turned inwards. The cause is probably due to femoral anteversion.

Annibale Carracci’s sketch of a boy with a hunchback conveys the boy’s emotions remarkably well. The possibilities of the underlying cause of the spinal deformity and its neurologic complications are discussed.

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The article focuses on the challenges faced by ensemble directors of smaller bands and orchestras, particularly in terms of selecting suitable repertoire that caters to both advanced and developing musicians while working with limited instrumentation. It emphasizes the importance of evaluating the ensemble's needs and suggests considering flexible ensemble arrangements to provide growth opportunities for students of varying skill levels and instrumentation constraints.