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Nonserotypeable isolates predominate in epidemic conjunctivitis caused by Streptococcus pneumoniae. Previous evaluations of outbreaks of pneumococcal conjunctivitis have relied on epidemiologic factors and the nontypeability of the isolates to infer that a single clone was involved. In the present study, BOX-polymerase chain reaction DNA analysis was used to characterize nonserotypeable S. pneumoniae isolated by conjunctival culture during a recent conjunctivitis outbreak and to compare these isolates with those from outbreaks described earlier. The recent outbreak was caused by a single pneumococcal clone. Outbreaks in separate parts of the United States in 1980-1981 were all caused by the same clone. Cluster analysis revealed a high degree of genetic relatedness among isolates causing conjunctivitis compared with that among other nonserotypeable S. pneumoniae, with the closest relatedness being found among the 1996 and 1980-1981 conjunctival isolates. [ABSTRACT FROM AUTHOR]

This paper illustrates the benefits of long-term monitoring of soil and vine health in Craggy Range’s Te Muna vineyard in the Martinborough region of New Zealand. The soils at Te Muna are formed on two river terraces. The higher and older terrace, planted to Pinot Noir, is very gravelly; the lower and younger terrace, planted to Sauvignon Blanc, contains more silt and very fine sand. Both terraces are freely drained. Soil pH, organic C and available P were monitored in selected blocks on both terraces. Under current management that includes cover crops and sheep grazing in winter, soil organic C has been stable for 10 years. Because of the regular application of RPR and intermittent liming, soil pH (water) has risen from c.5.5 to 6.5–7. Values for soil available P, measured by Olsen bicarbonate and Mehlich-3 extractions, diverged over time. The Olsen test indicated satisfactory P levels: conversely, the Mehlich test showed P values rising to very high levels, confirming Western Australian experience that this acid extraction is unsuitable for soils treated with RPR. Petiole and leaf blade P concentrations confirmed these results, but they showed greater interannual variation than the soil P measurements. Overall, the long-term sustainability of the vineyard should be assured.

Abstract Background Ulceration of the oesophageal squamous mucosa (ulcerative oesophagitis) is a pathological manifestation of gastro-oesophageal reflux disease, and is a major risk factor for the development of Barrett’s oesophagus. Barrett’s oesophagus is characterised by replacement of reflux-damaged oesophageal squamous epithelium with a columnar intestinal-like epithelium. We previously reported discovery of microRNAs that are differentially expressed between oesophageal squamous mucosa and Barrett’s oesophagus mucosa. Now, to better understand early steps in the initiation of Barrett’s oesophagus, we assessed the expression, location and function of these microRNAs in oesophageal squamous mucosa from individuals with ulcerative oesophagitis. Methods Quantitative real-time PCR was used to compare miR-21, 143, 145, 194, 203, 205 and 215 expression levels in oesophageal mucosa from individuals without pathological gastro-oesophageal reflux to individuals with ulcerative oesophagitis. Correlations between microRNA expression and messenger RNA differentiation markers BMP-4, CK8 and CK14 were analyzed. The cellular localisation of microRNAs within the oesophageal mucosa was determined using in-situ hybridisation. microRNA involvement in proliferation and apoptosis was assessed following transfection of a human squamous oesophageal mucosal cell line (Het-1A). Results miR-143, miR-145 and miR-205 levels were significantly higher in gastro-oesophageal reflux compared with controls. Elevated miR-143 expression correlated with BMP-4 and CK8 expression, and elevated miR-205 expression correlated negatively with CK14 expression. Endogenous miR-143, miR-145 and miR-205 expression was localised to the basal layer of the oesophageal epithelium. Transfection of miR-143, 145 and 205 mimics into Het-1A cells resulted in increased apoptosis and decreased proliferation. Conclusions Elevated miR-143, miR-145 and miR-205 expression was observed in oesophageal squamous mucosa of individuals with ulcerative oesophagitis. These miRNAs localised to the basal layer of the oesophageal epithelium. They reduced proliferation and increased apoptosis, and may play roles in regulating epithelial restoration in response to injury caused by gastro-oesophageal reflux.

Abstract Background Proton pump inhibitor (PPI) medication and surgical fundoplication are used for the control of gastro-oesophageal reflux in patients with Barrett's oesophagus, but differ in their effectiveness for both acid and bile reflux. This might impact on the inflammatory processes that are associated with progression of Barrett's oesophagus to cancer, and this may be evident in the gene expression profile and microRNA expression pattern in Barrett's oesophagus mucosa. We hypothesised that two miRNAs with inflammatory and oncogenic roles, miR-101 and miR-196a, are differentially expressed in Barrett's oesophagus epithelium in patients with reflux treated medically vs. surgically. Findings Mucosal tissue was obtained at endoscopy from patients with Barrett's oesophagus whose reflux was controlled by proton pump inhibitor (PPI) therapy (n = 20) or by fundoplication (n = 19). RNA was extracted and the expression of miR-101 and miR-196a was measured using real-time reverse transcription - polymerase chain reaction. There were no significant differences in miR-101 and miR-196a expression in Barrett's oesophagus epithelium in patients treated by PPI vs. fundoplication (p = 0.768 and 0.211 respectively). Secondary analysis showed a correlation between miR-196a expression and Barrett's oesophagus segment length (p = 0.014). Conclusion The method of reflux treatment did not influence the expression of miR-101 and miR-196a in Barrett's oesophagus. This data does not provide support to the hypothesis that surgical treatment of reflux better prevents cancer development in Barrett's oesophagus. The association between miR-196a expression and Barrett's oesophagus length is consistent with a tumour promoting role for miR-196a in Barrett's oesophagus.

Abstract Background Metallothionein 3 (MT3) inhibits growth in a variety of cell types. We measured MT3 gene expression by RT-PCR, and DNA methylation in the MT3 promoter by combined bisulphite restriction analysis, in four oesophageal cancer cell lines and the resected oesophagus from 64 patients with oesophageal squamous cell carcinoma (SCC). Results MT3 expression was not detected in one of the four oesophageal cell lines. The MT3 promoter was methylated in all of the oesophageal cell lines, but the degree of methylation was greater in the non-expressing cell line. After treatment with 5-aza-2'-deoxycytidine there was a reduction in the degree of methylation, and an increase in MT3 expression, in each of the cell lines (p < 0.01). Methylation was detected in 52% (33 of 64) of primary SCC and 3% (2 of 62) of histologically normal resection margins. MT3 expression was measured in 29 tumours, 17 of which had methylation of MT3. The expression of MT3 was significantly less in the methylated tumours compared to either the unmethylated tumours (p = 0.03), or the matched margin (p = 0.0005). There was not a significant difference in MT3 expression between the tumour and the margin from patients with unmethylated tumour. No correlations were observed between methylation of MT3 and survival time, patient age, gender, smoking or drinking history, tumour stage, volume, or lymph node involvement. Conclusion We conclude that MT3 expression is frequently down-regulated in oesophageal SCC, by DNA methylation, but that this is not a prognostic indicator.

Objective:  This study aimed to describe patient characteristics, satisfaction, and outcome measures for patients undergoing outpatient cervical ripening., Study Design:  A retrospective cohort study using electronic health record data from March 2020 to March 2022 from a large health system. The sample included patients with a low-risk singleton pregnancy undergoing outpatient cervical ripening with either an osmotic dilator or Foley balloon catheter. A subset of patients completed satisfaction surveys. Frequencies and means were used to describe the population and conduct comparisons by device type. Inverse probability of treatment weighted estimates were generated to address baseline differences between patients in the two device groups., Results:  Outpatient cervical ripening was completed by 120 patients (80 osmotic dilators and 40 Foley balloon catheters). The mean time from insertion to inpatient admission was 16.2 ± 4.8 hours. The mean change in simplified Bishop score (SBS) was 1.8 ± 1.4 and the mean change in dilation was 1.8 ± 1.1 cm. There were no differences in the amount of cervical change by device type. Patients returned earlier than planned 16.7% of the time, primarily for contractions or rupture of membranes. Following outpatient cervical ripening, the time from admission to delivery was 19.9 ± 10.3 hours, with no difference by device type. Vaginal delivery occurred for 74.8% of patients. Patients reported overall satisfaction with the outpatient cervical ripening experience, with the highest satisfaction among those with osmotic dilators. Patients with both device types stated they would recommend outpatient cervical ripening to others, and experienced low levels of stress and discomfort at home prior to hospital admission., Conclusion:  Patients participating in outpatient cervical ripening with osmotic dilators or Foley balloon catheters experienced clinically meaningful changes in dilation and SBSs while at home and reported general satisfaction with the outpatient program experience., Key Points: · Outpatient use of osmotic dilators or Foley balloon catheters improved Bishop scores.. · Patient and device complications were comparable to other research findings.. · Patients reported overall satisfaction with outpatient cervical ripening.., Competing Interests: None declared., (Thieme. All rights reserved.)

Background: Anaplastic sarcoma of the kidney (ASK) is a DICER1-related neoplasm first identified as a distinctive tumor type through the evaluation of unusual cases of putative anaplastic Wilms tumors. Subsequent case reports identified the presence of biallelic DICER1 variants as well as progression from cystic nephroma, a benign DICER1-related neoplasm. Despite increasing recognition of ASK as a distinct entity, the optimal treatment remains unclear., Methods: Individuals with known or suspected DICER1-related tumors including ASK were enrolled in the International Pleuropulmonary Blastoma/DICER1 Registry. Additionally, a comprehensive review of reported cases of ASK was undertaken, and data were aggregated for analysis with the aim to identify prognostic factors and clinical characteristics to guide decisions regarding genetic testing, treatment, and surveillance., Results: Ten cases of ASK were identified in the Registry along with 37 previously published cases. Staging data, per Children's Oncology Group guidelines, was available for 40 patients: 13 were stage I, 12 were stage II, 10 were stage III, and five were stage IV. Outcome data were available for 37 patients. Most (38 of 46) patients received upfront chemotherapy and 14 patients received upfront radiation. Two-year event-free survival (EFS) for stage I-II ASK was 81.8% (95% confidence interval [CI]: 67.2%-99.6%), compared with 46.6% EFS (95% CI: 24.7%-87.8%) for stage III-IV (p = .07). Two-year overall survival (OS) for stage I-II ASK was 88.9% (95% CI: 75.5%-100.0%), compared with 70.0% (95% CI: 46.7%-100.0%) for stage III-IV (p = .20). Chemotherapy was associated with improved EFS and OS with hazard ratios of 0.09 (95% CI: 0.02-0.31) and 0.08 (95% CI: 0.02-0.42), respectively., Conclusion: ASK is a rare DICER1-related renal neoplasm. In the current report, we identify clinical and treatment-related factors associated with outcome including the importance of chemotherapy in treating ASK. Ongoing data collection and genomic analysis are indicated to optimize outcomes for children and adults with these rare tumors., (© 2024 Wiley Periodicals LLC.)

We report a highly cross- and atroposelective coupling between ortho -(chloro)arylphosphine oxides and ortho -(bromo)aryl ethers. This previously unknown asymmetric nickel-catalyzed reaction offers a direct route to highly enantioenriched axially chiral biaryl monophosphine oxides that are difficult to access by other means. These products can be readily reduced to generate chiral MOP-type ligands bearing complex skeletal backbones. The utility of these chiral ligands in asymmetric catalysis is also demonstrated.

Water striders are abundant in areas with high humidity and rainfall. Raindrops can weigh more than 40 times the adult water strider and some pelagic species spend their entire lives at sea, never contacting ground. Until now, researchers have not systematically investigated the survival of water striders when impacted by raindrops. In this experimental study, we use high-speed videography to film drop impacts on water striders. Drops force the insects subsurface upon direct contact. As the ensuing crater rebounds upward, the water strider is propelled airborne by a Worthington jet, herein called the first jet. We show the water strider's locomotive responses, low density, resistance to wetting when briefly submerged, and ability to regain a super-surface rest state, rendering it impervious to the initial impact. When pulled subsurface during a second crater formation caused by the collapsing first jet, water striders face the possibility of ejection above the surface or submersion below the surface, a fate determined by their position in the second crater. We identify a critical crater collapse acceleration threshold ∼ 5.7 gravities for the collapsing second crater which determines the ejection and submersion of passive water striders. Entrapment by submersion makes the water strider poised to penetrate the air-water interface from below, which appears impossible without the aid of a plastron and proper locomotive techniques. Our study is likely the first to consider second crater dynamics and our results translate to the submersion dynamics of other passively floating particles such as millimetric microplastics atop the world's oceans., Competing Interests: Competing interests statement:The authors declare no competing interest.

Background: The medical profession has been slow in embracing email as a means of improving communication with patients., Aims: To explore the attitudes, practices and experiences of senior medical specialists towards email communication with their patients., Methods: A cross-sectional qualitative interview of 30 medical staff specialists employed by Canberra Health Services, administered through one-on-one interviews conducted between June and August 2020 (several months into the COVID-19 pandemic). Main outcome measures are the comments extracted from the interviews that were categorised into five domains: (i) integration of email use with patients; (ii) issues addressed through email; (iii) benefits of email communication; (iv) concerns and barriers to email communication; and (v) practice pointers for email use with patients., Results: Regular email correspondence with patients was not widespread. The main benefits identified were improved efficiency and flexibility, especially in the context of managing chronic disease and patient follow up. Participants also identified barriers, including time commitments, privacy and confidentiality, patient expectations and potential for misuse. Most participants were hesitant to endorse email with patients in their practices, citing concerns over the utility and safety of the medium and lack of established protocols and recommendations for email usage., Conclusions: There is a want and need for comprehensive and accessible professional guidance on email use with patients. Our results indicate opportunities to inform good clinical practice in respect of doctor-patient relationships, clinical workloads and risk management. There is also a need for formal guidelines on emailing with patients. The COVID-19 pandemic has heightened the need for such guidelines., (© 2021 Royal Australasian College of Physicians.)

The preparation of tertiary nitroalkanes via the nickel-catalyzed alkylation of secondary nitroalkanes using aliphatic iodides is reported. Previously, catalytic access to this important class of nitroalkanes via alkylation has not been possible due to the inability of catalysts to overcome the steric demands of the products. However, we have now found that the use of a nickel catalyst in combination with a photoredox catalyst and light leads to much more active alkylation catalysts. These can now access tertiary nitroalkanes. The conditions are scalable as well as air and moisture tolerant. Importantly, reduction of the tertiary nitroalkane products allows rapid access to α-tertiary amines.

General conditions for the Hiyama-Denmark cross-coupling of tetrasubstituted vinyl silanes and aryl halides are reported. Prior reports of Hiyama-Denmark reactions of tetrasubstituted vinyl silanes have required the use of vinyl silanols or silanolates, which are challenging to handle, or internally activated vinyl silanes, which lack structural generality. Now, unactivated tetrasubstituted vinyl silanes, bearing bench-stable tetraorganosilicon centers, and aryl halides can be coupled. The key to this discovery is the identification of dimethyl(5-methylfuryl)vinylsilanes as bench stable and easily prepared cross-coupling partners that are readily activated under mild conditions in Hiyama-Denmark couplings. These palladium-catalyzed cross-couplings proceed well with aryl chlorides, though aryl bromides and iodides are also tolerated, and the reactions display high stereospecificity in the formation of tetrasubstituted alkenes. In addition, only a mild base (KOSiMe 3 ) and common solvents (THF/DMA) are required, and importantly toxic additives (such as 18-crown-6) are not needed. We also show that these conditions are equally applicable to Hiyama-Denamrk coupling of trisubstituted vinyl silanes., Competing Interests: The authors declare no competing financial interest.

High-Throughput Experimentation (HTE) workflows are efficient means of surveying a broad array of chiral catalysts in the development of catalytic asymmetric reactions. However, use of traditional HPLC-UV/vis methodology to determine enantiomeric excess (ee) from the resulting reactions is often hampered by co-elution of other reaction components, resulting in erroneous ee determination when crude samples are used, and ultimately requiring product isolation prior to ee analysis. In this study, using four published reactions selected as model systems, we demonstrate that the use of LC-MS, SFC-MS, and selected ion monitoring (SIM) mass chromatography provides a highly accurate means to determine ee of products in crude reaction samples using commonplace, low-cost MS detectors. By using ion selection, co-eluting signals can be deconvoluted to provide accurate integrations of the target analytes. We also show that this method is effective for samples lacking UV/vis chromophores, making it ideal for HTE workflows in asymmetric catalysis.

Introduction: Uterine incision based on the placental location in open maternal-fetal surgery (OMFS) has never been evaluated in regard to maternal or fetal outcomes., Objective: The aim of this study was to investigate whether an anterior placenta was associated with increased rates of intraoperative, perioperative, antepartum, obstetric, or neonatal complications in mothers and babies who underwent OMFS for fetal myelomeningocele (fMMC) closure., Methods: Data from the international multicenter prospective registry of patients who underwent OMFS for fMMC closure (fMMC Consortium Registry, December 15, 2010-June 31, 2019) was used to compare fetal and maternal outcomes between anterior and posterior placental locations., Results: The placental location for 623 patients was evenly distributed between anterior (51%) and posterior (49%) locations. Intraoperative fetal bradycardia (8.3% vs. 3.0%, p = 0.005) and performance of fetal resuscitation (3.6% vs. 1.0%, p = 0.034) occurred more frequently in cases with an anterior placenta when compared to those with a posterior placenta. Obstetric outcomes including membrane separation, placental abruption, and spontaneous rupture of membranes were not different among the 2 groups. However, thinning of the hysterotomy site (27.7% vs. 17.7%, p = 0.008) occurred more frequently in cases of an anterior placenta. Gestational age (GA) at delivery (p = 0.583) and length of stay in the neonatal intensive care unit (p = 0.655) were similar between the 2 groups. Fetal incision dehiscence and wound revision were not significantly different between groups. Critical clinical outcomes including fetal demise, perinatal death, and neonatal death were all infrequent occurrences and not associated with the placental location., Conclusions: An anterior placental location is associated with increased risk of intraoperative fetal resuscitation and increased thinning at the hysterotomy closure site. Individual institutional experiences may have varied, but the aggregate data from the fMMC Consortium did not show a significant impact on the GA at delivery or maternal or fetal clinical outcomes., (© 2021 S. Karger AG, Basel.)

The first total synthesis of the natural product impatien A is described. This concise synthesis features an aza-Heck cyclization to construct the complex spirocyclic ring system and provides a rare example of the use of aza-Heck cyclizations in complex molecule synthesis. To enable this key cyclization of an electrophilic nitrogen atom with a tetrasubstituted alkene, we utilized high-throughput experimentation to identify a new ligand and ultimately deliver impatien A in seven steps from known compounds.

The synthesis of 1,1-diboryl alkenes from terminal alkenes is reported. 1,1-Regioselective addition is observed for both conjugated and unconjugated alkenes, allowing for a single method to prepare a wide range of 1,1-diboryl alkenes.

The palladium-catalysed tandem aza-Heck-Suzuki and aza-Heck-carbonylation reactions of O -phenyl hydroxamic ethers are reported. These formal alkene carboamination reactions provide highly versatile access to wide range complex, stereogenic secondary lactams and exhibit outstanding functional group tolerance and high diastereoselectivity., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report an asymmetric homocoupling of ortho- (iodo)arylphosphine oxides and ortho -(iodo)arylphosphonates resulting in highly enantioenriched axially chiral bisphosphine oxides and bisphosphonates. These products are readily converted to enantioenriched biaryl bisphosphines without need for chiral auxiliaries or optical resolution. This provides a practical route for the development of previously uninvestigated atroposelective biaryl bisphosphine ligands. The conditions have also proven effective for asymmetric dimerization of other, non-phosphorus-containing aryl halides.

Using a commercially available, inexpensive, and abundant copper catalyst system, an efficient α-functionalization of nitroalkanes with propargyl bromides is now established. This mild and robust method is highly functional group tolerant and provides straightforward access to complex secondary and tertiary homopropargylic nitroalkanes. Moreover, the utility of these α-propargylated nitroalkanes is demonstrated through downstream functionalization to biologically relevant, five-membered N -heterocycles such as pyrroles and 2-pyrrolines.

We report a palladium-catalyzed, three-component carbosilylation reaction of internal symmetrical alkynes, silicon electrophiles, and primary alkyl zinc iodides. Depending on the choice of ligand, stereoselective synthesis of either cis- or trans -tetrasubstituted vinyl silanes is possible. We also demonstrate conditions for the Hiyama cross-coupling of these products to prepare geometrically defined tetrasubstituted alkenes.

Phosphonate-directed ortho C-H borylation of aromatic phosphonates is reported. Using simple starting materials and commercially accessible catalysts, this method provides steady access to o -phosphonate arylboronic esters bearing pendant functionality and flexible substitution patterns. These products serve as flexible precursors for a variety of highly substituted phosphoarenes, and in situ downstream functionalization of the products is described.

Biological molecules can be obtained from natural sources or from commercial waste streams and can serve as effective feedstocks for a wide range of polymer products. From foams to epoxies and composites to bulk plastics, biomolecules show processability, thermal stability, and mechanical adaptations to fulfill current material requirements. This paper summarizes the known bio-sourced (or bio-derived), environmentally safe, thermo-oxidative, and flame retardant (BEST-FR) additives from animal tissues, plant fibers, food waste, and other natural resources. The flammability, flame retardance, and-where available-effects on polymer matrix's mechanical properties of these materials will be presented. Their method of incorporation into the matrix, and the matrices for which the BEST-FR should be applicable will also be made known if reported. Lastly, a review on terminology and testing methodology is provided with comments on future developments in the field.

We report the synthesis of unsaturated silacycles via an intramolecular silyl-Heck reaction. Using palladium catalysis, silicon electrophiles tethered to alkenes cyclize to form 5- and 6-membered silicon heterocycles. The effects of alkene substitution and tether length on the efficiency and regioselectivity of the cyclizations are described. Finally, through the use of an intramolecular tether, the first examples of disubstituted alkenes in silyl-Heck reactions are reported., Competing Interests: The authors declare no competing financial interest.

For the first time, an aza-Heck cyclization that allows the preparation of indoline scaffolds is described. Using N-hydroxy anilines as electrophiles, which can be easily accessed from the corresponding nitroarenes, this method provides indolines bearing pendant functionality and complex ring topologies. Synthesis of challenging indolines, such as those bearing fully substituted carbon atoms at C2, is also possible using this method., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

At the advent of cross-coupling chemistry, carbon electrophiles based on halides or pseudohalides were the only suitable electrophilic coupling partners. Almost two decades passed before the first cross-coupling reaction of heteroatom-based electrophiles was reported. Early work by Murai and Tanaka initiated investigations into silicon electrophiles. Narasaka and Johnson pioneered the way in the use of nitrogen electrophiles, while Suginome began the exploration of boron electrophiles. The chemistry reviewed within provides perspective on the use of heteroatomic electrophiles, specifically silicon-, nitrogen-, boron-, oxygen-, and phosphorus-based electrophiles in transition-metal catalyzed cross-coupling. For the purposes of this review, a loose definition of cross-coupling is utilized; all reactions minimally proceed via an oxidative addition event. Although not cross-coupling in a traditional sense, we have also included catalyzed reactions that join a heteroatomic electrophile with an in situ generated nucleophile. However, for brevity, those involving hydroamination or C-H activation as a key step are largely excluded. This work includes primary references published up to and including October 2018.

A general catalytic method for asymmetric C-alkylation of nitroalkanes using nickel catalysis is described. This method enables the formation of highly enantioenriched β-nitroamides from readily available α-bromoamides using mild reaction conditions that are compatible with a wide range of functional groups. When combined with subsequent reactions, this method allows access to highly enantioenriched products with nitrogen-bearing fully substituted carbon centers.

Background: Thousands of medical students undertake international medical electives each year. These students face potentially substantial health and safety risks as well as educational and ethical challenges and therefore should undertake their electives within well-structured and coordinated programs., Methods: We conducted a qualitative systematic review based on a pre-determined protocol. Relevant publications and guidelines relating to international medical electives were identified through a review of the literature using on-line search engines, principally PubMed. We then conducted a systematic qualitative synthesis to extract relevant publications. Finally, the literature was organized according to themes, with the aim of developing a structured set of Recommendations for Implementation for program coordinators., Results: A wide range of important issues were identified which were categorized into seven themes upon which recommendations were made principally for the benefit of program coordinators: Responsibilities; General policies; Travel advisories; Occupational risk assessment; Funding & finances, Pre-departure training programs; and Post-return debriefing and screening., Conclusions: Recommendations for program coordinators on the health and safety of medical students while on international medical electives have been sourced from existing guidelines and relevant publications. There was considerable consensus from the literature and as such these synthesised recommendations could form the basis for internationally accepted standards for elective placement program coordinators., Competing Interests: Not applicable.Not applicable.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Vertical impacts of spheres on clean water have been the subject of numerous water entry investigations characterizing cavity formation, splash crown ascension and Worthington jet stability. Here, we establish experimental protocols for examining splash dynamics when smooth free-falling spheres of varying wettability, mass, and diameter impact the free surface of a deep liquid pool modified by thin penetrable fabrics and liquid surfactants. Water entry investigations provide accessible, easily assembled and executed experiments for studying complex fluid mechanics. We present herein a tunable protocol for characterizing splash height, flow separation metrics, and impactor kinematics, and representative results which might be acquired if reproducing our approach. The methods are applicable when characteristic splash dimensions remain below approximately 0.5 m. However, this protocol may be adapted for greater impactor release heights and impact velocities, which augurs well for translating results to naval and industry applications.

The direct borylation of disubstituted alkenes is reported. These conditions allow for the conversion of a variety 1,1- and 1,2-disubstituted alkenes to trisubstituted alkenyl boronic esters with outstanding yields and excellent E/ Z selectivities. The utility of this reaction has been demonstrated with several downstream functionalization reactions, which allow access to diverse, stereodefined, functionalized olefins. Mechanistic studies are consistent with a boryl-Heck pathway.

The synthesis of unsaturated, unprotected imidazolidinones via an aza-Heck reaction is described. This palladium-catalyzed process allows for the cyclization of N-phenoxy ureas onto pendant alkenes. The reaction has broad functional group tolerance, can be applied to complex ring topologies, and can be used to directly prepare mono- and bis-unprotected imidazolidinones. By addition of Bu 4 NI, dihydroimidazolones can be accessed from the same starting materials. Improved conditions for preparing unsaturated, unprotected lactams are also reported., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We describe a case of nasal myiasis due to Musca domestica in a 97-year-old Peruvian farmer with a previously undiagnosed mucocutaneous leishmaniasis. Initial attempts to remove the fly larvae using manual extraction with a toothed forceps and normal saline irrigation were unsuccessful. On subsequent nasal irrigation with ivermectin solution, the patient self-expulsed approximately 50 larvae within 15 min. He also received a course of oral ivermectin. A post-treatment CT scan revealed clear sinuses. Here, we propose that ivermectin irrigation is a simple and effective treatment for nasal myiasis., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Using a palladium catalyst supported by DrewPhos, the alkylation of monochlorosilanes with primary and secondary alkyl-magnesium halides is now possible. Arylation with sterically demanding aromatic magnesium halides is also enabled. This transformation overcomes the high bond strength of the Si-Cl bond (113 kcal/mol) and is a rare example of a transition-metal catalyzed process involving its activation. Due to the availability of both chlorosilanes and organomagnesium halide reagents, this method allows for the preparation of a wide range of alkyl and aryl silanes., Competing Interests: The authors declare the following competing financial interests: UD has applied for a provisional patent related to this methodology.

Studies of the silyl-Heck reaction aimed at identifying active palladium complexes have revealed a new species that is formed in situ. This complex has been identified as the palladium iodide dimer, [(JessePhos)PdI 2 ] 2 , which has been found to be a competent single-component precatalyst for the silyl-Heck reaction. This complex is easily prepared and is temperature, moisture, and air stable. Additionally, this precatalyst provides higher activity and greater reproducibility compared to previous systems.

Since the discovery of the Heck reaction in the early seventies, this reaction has become a powerful tool in synthetic organic chemistry. By employing heteroatomic instead of traditional carbon electrophiles, the Heck reaction shows an intriguing flexibility. These "hetereoatomic-Heck reactions" reinvigorate the area, offering new routes to highly useful synthetic precursors and structural motifs present in biologically active compounds. This microreview focuses on early developments leading to the heteroatomic-Heck reactions (silyl-Heck, boryl-Heck and intramolecular aza-Heck), current state of the emerging area, as well as that of a few related processes.

Enabled by nickel catalysis, a mild and general catalytic method for C-alkylation of nitroalkanes with unactivated alkyl iodides is described. Compatible with primary, secondary, and tertiary alkyl iodides; and tolerant of a wide range of functional groups, this method allows rapid access to diverse nitroalkanes.

We report the first example of a silyl-Negishi reaction between secondary zinc organometallics and silicon electrophiles. This palladium-catalyzed process provides direct access to alkyl silanes. The delicate balance of steric and electronic parameters of the employed DrewPhos ligand is paramount to suppressing isomerization and promoting efficient and selective cross-coupling.

Using a commercially available Umemoto's reagent, the metal-free trifluoromethylation of nitroalkanes is now possible. This method provides a general, high-yielding synthesis of α-(trifluoromethyl)nitroalkanes. The quaternary α-(trifluoromethyl)nitroalkanes obtained from this transformation can be elaborated to a variety of complex nitrogen-containing molecules, including α-(trifluoromethyl)amines.

Nonresonant laser vaporization combined with high-resolution electrospray time-of-flight mass spectrometry enables analysis of a casing after discharge of a firearm revealing organic signature molecules including methyl centralite (MC), diphenylamine (DPA), N-nitrosodiphenylamine (N-NO-DPA), 4-nitrodiphenylamine (4-NDPA), a DPA adduct, and multiple unidentified features not observed in previous mass spectral measurements. Collision-induced dissociation measurements of unknown GSR signature ions reveals inorganic barium and derivatives BaOH, BaOHCH 3 , BaCH 3 COO remaining from the primer. Both hydrophilic and hydrophobic signatures are detected using water-methanol electrospray solution. Offline principal component analysis and discrimination of the laser electrospray mass spectral (LEMS) measurements resulted in perfect classification of the gun shot residue with respect to the manufacturer. Principal component analysis of recycled and reloaded casings resulted in classification of the penultimate manufacturer with an accuracy of 89%.

The preparation of unsaturated secondary lactams via the palladium-catalyzed cyclization of O-phenyl hydroxamates onto a pendent alkene is reported. This method provides rapid access to a broad range of lactams that are widely useful building blocks in alkaloid synthesis. Mechanistic studies support an aza-Heck-type pathway.

The oxidative copper-catalyzed cross-coupling of functionalized alkyl boronic esters with primary amides is reported. Through the identification of appropriate diketimine ligands, conditions for efficient coupling of both primary and secondary alkyl boronic esters with diverse primary amides, including acetamide, have been developed., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We report the first example of a boryl-Heck reaction using an electrophilic boron reagent. This palladium-catalyzed process allows for the conversion of terminal alkenes to trans-alkenyl boronic esters using commercially available catecholchloroborane (catBCl). In situ transesterification allows for rapid access to a variety of boronic esters, amides, and other alkenyl boron adducts.