The African Light Source: history, context and future.

The African Light Source (AfLS) project is now almost eight years old. This article assesses the history, current context and future of the project. There is by now considerable momentum in building the user community, including deep training, facilitating access to current facilities, growing the scientific output, scientific networks and growing the local laboratory-scale research infrastructure. The Conceptual Design Report for the AfLS is in its final editing stages. This document specifies the socio-economic and scientific rationales and the technical aspects amongst others. The AfLS is supported by many national and Pan-African scientific professional bodies and voluntary associates across many scientific disciplines, and there are stakeholders throughout the continent and beyond. The current roadmap phases have expanded to include national and Pan-African level conversations with policy makers through new Strategic Task Force groups. The document summarizes this progress and discusses the future of the project.

Membrane vesicles of Lactobacillus gasseri ATCC 19992 disrupt biofilms of vaginal pathogens.

Membrane vesicles (MVs) are bioactive, nano-sized entities produced by all organisms. MVs of L. gasseri ATCC 19992 were isolated and their effect on the biofilms of vaginal pathogens, G. vaginalis and S. aureus was studied. The L. gasseri MVs resulted in significant disruption of biofilms of the vaginal pathogens.

Pancreaticoduodenectomy: Outcomes of a complex surgical procedure from a developing country.

BACKGROUND: Pancreaticoduodenectomy (PD) plays an integral part in the management of pancreatic, periampullary and duodenal cancers, along with a few other pathologies of this region. Despite advances in surgery PD continues to have significant morbidity and noteworthy mortality. The aim of this study is to provide an in-depth report on the patient characteristics, indications and the outcomes of PD) in a tertiary cancer hospital in Pakistan. MATERIALS AND METHODS: The study population included patients who underwent PD between January 1, 2014 and march 31, 2019, at Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH&RC) in Pakistan. The data was retrospectively analyzed from the Hospital Information System (HIS), which is a prospectively maintained patient electronic database of SKMCH&RC. Patient characteristics, procedural details and post-operative outcomes according to internationally accepted definitions were reported. RESULTS: A total of 161 patients underwent PD at our hospital in the study period at a median age of 53 years, ranging from 19 to 78 years. 62% of the patients were males while 37% were females. Jaundice was the most common presenting symptom (64.6%), followed by abdominal pain (26.7%). PD with pancreaticogastrostomy was performed in 110 patients (68.3%), while pancreaticojejunostomy was performed in the rest of the cohort. Surgical site infection (SSI) was observed in 64 patients (40%). The incidence of Pancreatic Fistula grade C based on the International Study Group on Pancreatic Fistula (ISGPF) definition was 7.45% (n = 12). The 30 days mortality rate was 3.1%. Median survival of the cohort was 21 ±1.13 months and disease-free survival was 16±2.62 months. CONCLUSION: PD can be performed with acceptable morbidity and mortality in a resource constrained country, as long as it is undertaken in a high-volume center. This is in keeping with data published from other well-reputed international centers.

M. S. Swaminathan (1925-2023).

Architect of India's green revolution.

Papillary Carcinoma of Breast: Clinicopathological Characteristics, Management, and Survival.

Objective: To study clinicopathological features, treatment strategies, and prognosis of papillary carcinoma of breast. Material and Methods. Data from 58 patients were retrospectively reviewed from January 2010 to December 2016. Four types of papillary carcinoma (on final resected specimen) were included, i.e., invasive papillary carcinoma (IPC), intracystic (encapsulated) papillary carcinoma (EPC), solid papillary carcinoma (SPC), and papillary DCIS (ductal carcinoma in situ). Various features of the four types were observed and compared. Results: Of the 58 patients, 8 were males (13.7%). The mean age at presentation was 61 years; the mean tumor size was 33 mm. The frequency of each histological type was as follows: IPC (n = 22/38%), EPC (n = 22/38%), SPC (n = 12/20.6%), and papillary DCIS (n = 2/3.4%). Only two patients were ER negative (both IPC). HER-2 Neu was positive in 3 patients only, out of which 2 died of progressive disease (one EPC and one IPC). LN metastasis was present in 3 (5%) patients (one in each of 1st three types) and only one died of bone metastasis that was also Her-2Neu positive. All patients underwent upfront surgery except two patients who had synchronous IDC on the contralateral side. Breast conservation surgery (BCS) was performed in 34 (58.6%) and mastectomy in 22 (37.9%) patients. 13 patients did not undergo invasive axillary staging; the rest of 43 (74%) patients did (32 sentinel biopsy and 11 axillary dissection). Chemotherapy was given to 18 patients (31%), mostly to IPC (n = 12). Only 2 patients had bone metastasis (one was IPC and one EPC). Cancer-related death was observed in 3 patients. For all groups combined, 5-year OS was 98% and DFS was 92%. Conclusion: Overall, papillary carcinoma of the breast has an excellent prognosis, even though less intense treatment modalities were used. It is still difficult to define the optimum management and avoid overtreatment, given the limited data in the literature.

Hamiltonian orbit structure of the set of paraxial optical systems.

In the paraxial regime of three-dimensional optics, two evolution Hamiltonians are equivalent when one can be transformed to the other modulo scale by similarity through an optical system. To determine the equivalence sets of paraxial optical Hamiltonians one requires the orbit analysis of the algebra sp(4, R) of 4 x 4 real Hamiltonian matrices. Our strategy uses instead the isomorphic algebra so(3, 2) of 5 x 5 matrices with metric (+1, +1, +1, -1, -1) to find four orbit regions (strata), six isolated orbits at their boundaries, and six degenerate orbits at their common point. We thus resolve the degeneracies of the eigenvalue classification.