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Background: Cleft lip and palate are the most common congenital craniofacial anomalies. They account for approximately 13% of all congenital anomalies. Objectives: To study the presentation of cleft lip and the early results of surgical repair among patients who presented to our centers. Methods: This was a hospital-based prospective cohort study of 72 patients who underwent cleft lip repair in Sudan. Results: The commonest age group was between 10–18 months. The male-to-female ratio was 2:1, and a family history of cleft lip was found in 2.8% of patients. The cleft lip was complete in 81.9%, incomplete in 12.5%, and hybrid in 5.6% of patients. Associated cleft palate was observed in 54 patients. Associated syndromes were found in 10 patients. The surgery was carried out in most patients at 9 months or less; in 4 patients, it was more than 18 months. Achievement of reasonable lip repair was moderate (50% collectively). High achievement was observed for criteria, such as accurate union (90.3%), and sub-moderate achievement in even vermillion border and cupid's bow (44%), low nose symmetry (30.6%), and quality of scar (18.1%). Early complications were reported at the rate of 13.9%. Patient satisfaction was 59.7%; however, the professionals showed higher satisfaction levels (66.7%). The anthropometric measurements of normal infants were moderately similar to those of the infants who underwent surgery. Conclusion: The patients with cleft lip showed early presentation, with a predominance of the male gender and left side pattern. The preliminary outcome of cleft lip repair was moderate, with variations in different criteria. Patient and professional satisfaction were above average.

Objective: To investigate the antifungal activity of voriconazole, with and without Kombucha tea culture, against Candida strains isolated from vulvovaginal candidiasis. Material and Methods: The study included 150 females, within child-bearing periods, complaining of valvovaginal candidiasis. Candida strains were isolated, and identified by conventional microbiological methods; and confirmed by Viteck-2 System. The sensitivity of the isolates to voriconazole was performed, via the Disc diffusion method. Resistant strains were then subjected to minimum inhibitory concentrations (MIC) investigation of voriconazole alone, and in combination with a Kombucha tea culture via the broth micro-dilution method in concentrations ranging from 0.0048 to 10 μg/ml. The ability of voriconazole, with and without Kombucha, to eradicate Candida biofilms were investigated using a crystal violet absorbance assay. Results: Eighty-nine strains were isolated. From these 60 isolates showed variable resistance patterns (57 were voriconazole resistant, and 3 had dose-dependent susceptability). Kombucha significantly decreased the MIC50 of voriconazole against all strains from 5 to 0.625 μg/ml (p-value

Background: Neoadjuvant chemotherapy (NACT) treatment has become the standard treatment for locally advanced breast cancer (LABC) in many centers worldwide. Objectives: This study evaluates the short-term response of patients with LABC to NACT and its impact on operability and the type of surgery. Patients and Methods: This is a descriptive analytical hospital-based study including 147 patients with LABC who were presented to Plastic and Reconstructive Surgery Unit at Soba University hospital (SUH), between January 2012 and December 2014, and were treated with NACT. Clinical and pathological responses to neoadjuvant chemotherapy were evaluated according to Union for International Cancer Control criteria, operability, and the type of surgery performed was also recorded. Results: All patients were females, the mean age was 43 ± 7 years, of them 53.7% were pre-menopausal, 51% presented with a breast lump, 19.7% with nipple discharge, and 19% with skin changes and ulceration. The mean initial tumor size was 7 cm ± SD. Following NACT, complete clinical response was reported in 30 patients (20.4%), partial clinical response in 92(62.6%), stable clinical response in 20 (13.6%), and five (3.4%) had progressive clinical response. Initial smaller tumors (size < 5 cm) showed a better clinical response to NACT as 76.7% of complete clinical response was achieved. Pathological complete response was achieved in 25(17%) patients, pathological partial response in 102(74.1%), and pathological stable disease in 13(8.8%). Following NACT, breast conserving surgery was performed in 78(53.1%) patients, Modified Radical Mastectomy in 64(43.5%), 25 of them had Latissimus Dorsi, and five patients were not offered surgery as they developed progressive disease during the study period. Conclusion: Following NACT, it was possible to perform surgery in more than 96% of patients with LABC.

The in-plane packing of gold (Au), polystyrene (PS), and silica (SiO2) spherical nanoparticle (NP) mixtures at a water-oil interface is investigated in situ by UV-vis reflection spectroscopy. All NPs are functionalized with carboxylic acid such that they strongly interact with amine-functionalized ligands dissolved in an immiscible oil phase at the fluid interface. This interaction markedly increases the binding energy of these nanoparticle surfactants (NPSs). The separation distance between the Au NPSs and Au surface coverage are measured by the maximum plasmonic wavelength (λmax) and integrated intensities as the assemblies saturate for different concentrations of non-plasmonic (PS/SiO2) NPs. As the PS/SiO2 content increases, the time to reach intimate Au NP contact also increases, resulting from their hindered mobility. λmax changes within the first few minutes of adsorption due to weak attractive inter-NP forces. Additionally, a sharper peak in the reflection spectrum at NP saturation reveals tighter Au NP packing for assemblies with intermediate non-plasmonic NP content. Grazing incidence small angle X-ray scattering (GISAXS) and scanning electron microscopy (SEM) measurements confirm a decrease in Au NP domain size for mixtures with larger non-plasmonic NP content. The results demonstrate a simple means to probe interfacial phase separation behavior using in situ spectroscopy as interfacial structures densify into jammed, phase-separated NP films.

Metal halide perovskite solar cells (PSCs) are infamous for their batch-to-batch and lab-to-lab irreproducibility in terms of stability and performance. Reproducible fabrication of PSCs is a critical requirement for market viability and practical commercialization. PSC irreproducibility plagues all levels of the community; from institutional research laboratories, start-up companies, to large established corporations. In this work, the critical function of atmospheric humidity to regulate the crystallization and stabilization of formamidinium lead triiodide (FAPbI3) perovskites is unraveled. It is demonstrated that the humidity content during processing induces profound variations in perovskite stoichiometry, thermodynamic stability, and optoelectronic quality. Almost counterintuitively, it is shown that the presence of humidity is perhaps indispensable to reproduce phase-stable and efficient FAPbI3-based PSCs.

We used data-driven methods to understand the formation of impurity phases in BiFeO3 thin-film synthesis through the sol-gel technique. Using a high-quality dataset of 331 synthesis procedures and outcomes extracted manually from 177 scientific articles, we trained decision tree models that reinforce important experimental heuristics for the avoidance of phase impurities but ultimately show limited predictive capability. We find that several important synthesis features, identified by our model, are often not reported in the literature. To test our ability to correctly impute missing synthesis parameters, we attempted to reproduce nine syntheses from the literature with varying degrees of "missingness". We demonstrate how a text-mined dataset can be made useful by informing new controlled experiments and forming a better understanding for impurity phase formation in this complex oxide system.

The combination of three highly complementary scientific domains is demonstrated to rationalize bismuth ferrite (BiFeO3 [BFO]) crystallization pathways: text mining to extract processing recipes from existing literature, in situ X-ray scattering to follow crystallization pathways of solution-processed thin films, and ab initio calculations to develop a comprehensive understanding of thin-film formation from thermodynamic principles. Multiferroic BFO is chosen as an example material of interest for technological applications to demonstrate and validate this combined approach. Thermodynamic modeling showed that the production of a short-lived intermediate bismutite phase (Bi2O2CO3) influences the energies of competing reactions forming BFO and Bi2Fe4O9, increasing the thermodynamic driving force toward the formation of BFO rather than Bi2Fe4O9 impurity phase over a large temperature window. The synergy between the scientific domains is exemplified through the rational guidelines developed for controlling high-quality and phase-pure material fabrication.

Triple cation, mixed halide perovskite compositions have been reported to be more thermally stable, exhibit fewer phase impurities, and show higher power conversion efficiency and better reproducibility than single cation perovskites. In this work, we explain the formation of Cs0.05FA0.81MA0.14Pb(I0.85Br0.15)3 via a multimodal in situ study combining structural information from synchrotron grazing-incidence wide-angle X-ray scattering (GIWAXS) and optical properties from photoluminescence (PL) spectroscopy with density functional theory calculations (DFT). The focus here is on the effects of the solvent and antisolvent during crystallization. The predominantly used solvents N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and the antisolvent chlorobenzene (CB) as well as the solvent-antisolvent-precursor interactions are investigated. Given the high elemental complexity and mutual interdependencies between solvent, antisolvent, and perovskite precursors, we found significant differences in the crystallization pathways. DMF-pure precursors show the formation of the DMF-containing intermediate phase and the nucleation of compositionally distinct perovskite phases, while when DMSO is added, only crystalline α- and δ-phases were found. In addition, the presence of DMSO helps the formation of α-perovskite. Coordination energy and bond order (BO) calculations support our experimental findings. Dripping of CB induces nucleation at room temperature, slows the α-phase formation rate, and appears to reduce the nucleation radius. These findings provide novel insights into solvent, antisolvent, and perovskite precursor interactions and their formation pathways. The complexity of interactions between solvents and reagents highlights the importance of understanding these effects to further improve the reproducibility and optimize processing conditions.

Using in situ photoluminescence measurements during the spin-coating and annealing steps, this study probes the formation of 2D layers on 3D triple cation perovskite films comparing phenylethylammonium and 2-thiophenemethylammonium iodide bulky cations. This study elucidates the formation mechanisms of the surface layers for both cases and reveals two regimes during 2D layer formation: a kinetic-driven and a thermodynamic-driven process. These driving forces result in different compositions of the 2D/3D interface for each treatment, namely, different ratios of pure 2D (n = 1) and quasi-2D (n > 1) structures. This study shows that a higher ratio of quasi-2D phases is more beneficial for device performance, as pure-2D layers may hamper current extraction. Due to a more evenly distributed formation energy profile among 2D and quasi-2D phases, highly concentrated 2-thiophenemethylammonium iodide appears to be more suited for effective surface passivation than its phenylethylammonium analog.

Yasser Bayoumi,1 Ayman AbdelSamie,2 Ahmed Abdelsaid,3 Aida Radwan4 1Radiation Oncology, 2Medical Oncology, 3Surgical Oncology, 4Medical Physics, National Cancer Institute, Cairo University, Cairo, Egypt Background/purpose: The aim was to evaluate the prognostic significance of postoperative radiotherapy (PORT) and surgical type on local recurrence-free survival (LRFS) and overall survival (OS) in triple-negative breast cancer (TNBC) in the Egyptian population. Patients and methods: We evaluated 111 patients with stage I–III TNBC diagnosed at our institute during the period from 2004 to 2009. Patients were stratified according to PORT into two groups: a PORT group and a non-PORT group. The influence of PORT and surgical type on LRFS and OS were evaluated. A cross-matching was done to the non-TNBC group of patients to compare the recurrence and survival rates between them and the studied group of TNBC patients. Results: The mean age of TNBC patients at diagnosis was 63±7 years. The majority of the patients had stage III disease (68.5%) and 73% had clinical or pathological positive lymph nodes. Sixty percent (67/111) of patients had modified radical mastectomy and 44/111 (40%) patients had breast-conserving treatment. PORT was given for 63% of patients, while systemic treatment was given in 89% of patients. At the time of analysis, 13 patients (11%) developed local recurrence: five of 70 (7%) in the PORT group and eight of 41 (19.5%) in the non-PORT group. Five-year LRFS for the whole group of patients was 88%±6%, which was significantly affected by PORT. The surgical type did not affect local recurrence significantly. Five-year OS for the whole group was 54%±8%. PORT and surgical type did not affect OS significantly (P-value 0.09 and 0.11, respectively). Five-year LRFS was 88%±6% and 90%±11% for TNBC and non-TNBC patients, respectively (P-value 0.8); however, OS for TNBC was significantly lower than for non-TNBC (P-value 0.04). Conclusion: TNBC is an aggressive entity compared with other non-TNBC, and these patients benefit from PORT significantly to decrease the risk of local recurrence in all stages. However, further large, prospective, randomized trials are warranted. Keywords: triple-negative breast cancer, postoperative radiotherapy, local recurrence-free survival, overall survival

Indoor photovoltaics are receiving tremendous attention due to the continuous development of the Internet of Things. The present study reports how the fast processing of the triple halide perovskite enables the retention of chlorine and the beneficial role of chlorine in enhancing the indoor light harvesting of a wide bandgap triple anion (TA) perovskite CH3NH3PbI2.6Br0.2Cl0.2. The kinetics of chlorine incorporation/escape investigated by in situ grazing incidence wide-angle X-ray scattering revealed the escape of chlorine after the first ten minutes of thermal annealing and the findings were corroborated with elemental analysis by wavelength dispersive X-ray spectroscopy. The best-performing TA perovskite indoor-photovoltaic device achieved a steady-state power conversion efficiency (PCE) of 25.1% with an output power density of ∼75 μW cm−2 under 1000 lux indoor illumination (0.3 mW cm−2 irradiance). Improved crystalline quality, reduced density of trap states and longer carrier lifetime were achieved by the triple anion alloying method. The detrimental role of the commonly used hole transporting layer (HTL) of Spiro-MeOTAD under indoor lighting conditions leading to J-V hysteresis was also investigated, which could then be effectively suppressed by replacing Spiro-MeOTAD with undoped P3HT. The optimized TA perovskite indoor PV cells were then successfully used to wirelessly power a textile fiber-based temperature sensor. The results from the present study demonstrate a novel route to incorporate chlorine effectively and maximize the steady state power output from halide perovskite indoor photovoltaic devices and their promising potential for the IoT industry.

Non-fullerene acceptors based organic solar cells represent the frontier of the field, owing to both the materials and morphology manipulation innovations. Non-radiative recombination loss suppression and performance boosting are in the center of organic solar cell research. Here, we developed a non-monotonic intermediate state manipulation strategy for state-of-the-art organic solar cells by employing 1,3,5-trichlorobenzene as crystallization regulator, which optimizes the film crystallization process, regulates the self-organization of bulk-heterojunction in a non-monotonic manner, i.e., first enhancing and then relaxing the molecular aggregation. As a result, the excessive aggregation of non-fullerene acceptors is avoided and we have achieved efficient organic solar cells with reduced non-radiative recombination loss. In PM6:BTP-eC9 organic solar cell, our strategy successfully offers a record binary organic solar cell efficiency of 19.31% (18.93% certified) with very low non-radiative recombination loss of 0.190 eV. And lower non-radiative recombination loss of 0.168 eV is further achieved in PM1:BTP-eC9 organic solar cell (19.10% efficiency), giving great promise to future organic solar cell research.

Lead-free halide double perovskites with enhanced stability have gained attention as a promising environmentally friendly alternative to lead-based halide perovskites. Amongst different halide double perovskites, Cs2AgBiBr6 has shown attractive optoelectronic properties and stability, making it a promising candidate for stable high-efficiency optoelectronic devices. Motivated by a data mining effort, we present here the effects of different processing strategies on the microstructure and thin-film formation dynamics of Cs2AgBiBr6. We apply some of the most successfully used solvent engineering approaches from the halide perovskite research to halide double perovskites, namely antisolvent- and additive-assisted synthesis. Using in situ spectroscopy and diffraction, the film formation of Cs2AgBiBr6 is investigated during spin coating, and the subsequent post-deposition thermal annealing. Dropping antisolvents during spin coating induces immediate supersaturation and crystallization of the wet film, whereas the time of dropping the antisolvent has implications on the film formation dynamics and the final microstructure. For additive (HBr)-assisted synthesis, we show how the addition of HBr affects colloid formation in solution and thus influences the crystallization pathway during thin-film processing. Finally, HBr additive simplifies synthesis in that it doesn't require solution and substrate preheating to obtain pinhole-free films even with higher thickness.

All-inorganic perovskites have emerged as promising photovoltaic materials due to their superior thermal stability compared to their heat-sensitive hybrid organic-inorganic counterparts. In particular, CsPbI2 Br shows the highest potential for developing thermally-stable perovskite solar cells (PSCs) among all-inorganic compositions. However, controlling the crystallinity and morphology of all-inorganic compositions is a significant challenge. Here, a simple, thermal gradient- and antisolvent-free method is reported to control the crystallization of CsPbI2 Br films. Optical in situ characterization is used to investigate the dynamic film formation during spin-coating and annealing to understand and optimize the evolving film properties. This leads to high-quality perovskite films with micrometer-scale grain sizes with a noteworthy performance of 17% (≈16% stabilized), fill factor (FF) of 80.5%, and open-circuit voltage (VOC ) of 1.27 V. Moreover, excellent phase and thermal stability are demonstrated even after extreme thermal stressing at 300 °C.

Chirality is a desired property in functional semiconductors for optoelectronic, catalytic, and spintronic applications. Here, introducing enantiomerically-pure 3-aminobutyric acid (3-ABA) into thin films of the 1D semiconductor dimethylammonium lead iodide (DMAPbI3) is found to result in strong circular dichroism (CD) in the optical absorption. X-ray diffraction and grazing incidence small angle X-ray scattering (GISAXS) are applied to gain molecular-scale insights into the chirality transfer mechanism, which is attributed to a chiral surface modification of DMAPbI3 crystallites. This study demonstrates that the CD signal strength can be controlled by the amino-acid content relative to the crystallite surface area. The CD intensity is tuned by the composition of the precursor solution and the spin-coating time, thereby achieving anisotropy factors (gabs) as high as 1.75 × 10–2. Grazing incidence wide angle scattering reveals strong preferential ordering that can be suppressed via tailored synthesis conditions. Different contributions to the chiroptical properties are resolved by a detailed analysis of the CD signal utilizing an approach based on the Mueller matrix model. This report of a novel class of chiral hybrid semiconductors with precise control over their optical activity presents a promising approach for the design of circularly polarized light detectors and emitters.

Wide-bandgap (WBG) mixed-halide perovskites as the front cell absorber are accomplishing perovskite-based tandem solar cells with over 29% power conversion efficiency. However, their large voltage deficits limit their ultimate performance. Only a handful of studies probe the fundamental mechanisms underlying the voltage deficits, which remain an unsolved challenge in the field. In this study, we investigate the formation dynamics and defect physics of WBG mixed-halide perovskites in contrast with their corresponding triiodide-based perovskites. Our results show that the inclusion of bromide introduced a halide homogenization process that occurs during the perovskite growth stage from an initial bromide-rich phase toward the final target stoichiometry. We further elucidated a physical model that correlates the role of bromide with the formation dynamics, defect physics, and eventual optoelectronic properties of the film. This work provides a fundamental and unique perspective toward understanding the performance-limiting factors affecting WBG mixed-halide perovskites.

Translating all-polymer solar cells from spin-coating to scalable roll-to-roll-compatible fabrication techniques is a critical step toward the application of organic photovoltaics at a scale. Techniques to control polymer crystallization and phase separation during solution printing are essential to obtain high-performance printed organic solar cells. Here, we demonstrate a novel solvent additive approach employing trace amounts of phthalates as additives to control polymer crystallinity and suppress unfavorable phase separation in a representative PTB7-Th/P(NDI2OD-2T) all-polymer solar cell. The best-performing additive increased the blade-coated device performance from 2.09 to 4.50% power conversion efficiency, an over twofold improvement, mitigating the loss in performance that is typically observed during process transfer from spin-coating to blade-coating. It is suggested that the improved device performance stems from a finer polymer phase-separation size and overall improved active layer morphology, evidenced by device characterization data and indirectly supported by grazing incidence wide-angle X-ray scattering analyses. Real-time X-ray diffraction measurements during blade-coating provide mechanistic insights and suggest that the dioctyl phthalate additive may act as a compatibilizer, reducing the demixing of the donor and acceptor polymer during film formation, enabling a smaller phase separation and improved performance. The structural diversity of the class of phthalate additives makes this simple yet effective concept promising for translating other all-polymer material systems to blade-coating and other scalable printing techniques.

Inspired by the fascinating class of hybrid organic-inorganic halide perovskite materials, halide double perovskites have emerged as non-toxic Pb-free contenders for application as active layers in optoelectronic devices. Heterovalent substitution of Pb2+ by non-toxic metal cations yields the double-perovskite structure, which allows for compositional flexibility. In fact, the compositional space is large, given that multiple cations and halides can be combined, resulting in >106 perovskite combinations. A starkly increasing number of stable halide double-perovskite compositions are theoretically predicted. The synthesis, however, lags behind, and many double perovskites are primarily synthesized as powder samples instead of thin films. The latter, however, are needed for thin-film devices such as solar cells, light-emitting devices, and thin-film transistors. Comparing the synthetic approaches successfully applied to hybrid perovskites to methods used for the fabrication of double perovskites, the latter are clearly in their very infancy. The question is whether solution engineering and compositional modification strategies can be exploited to match the exceptional optoelectronic properties of hybrid perovskites. This review is motivated by a text mining effort that illustrates not only the prevalence of powder over thin-film synthesis but also the discrepancy between the number of compositions experimentally realized and studied and the many predicted compositions. Here we summarize the synthesis aspects of halide double perovskites, and in particular of thin films, including deposition techniques and synthetic modifications to alter film properties.

Postfabrication surface treatment strategies have been instrumental to the stability and performance improvements of halide perovskite photovoltaics in recent years. However, a consensus understanding of the complex reconstruction processes occurring at the surface is still lacking. Here, we combined complementary surface-sensitive and depth-resolved techniques to investigate the mechanistic reconstruction of the perovskite surface at the microscale level. We observed a reconstruction toward a more PbI2-rich top surface induced by the commonly used solvent isopropyl alcohol (IPA). We discuss several implications of this reconstruction on the surface thermodynamics and energetics. Particularly, our observations suggest that IPA assists in the adsorption process of organic ammonium salts to the surface to enhance their defect passivation effects.

Perovskite solar cells have received substantial attention due to their potential for low-cost photovoltaic devices on flexible or rigid substrates. Thiocyanate (SCN)-containing additives, such as MASCN (MA = methylammonium), have been shown to control perovskite film crystallization and the film microstructure to achieve effective room-temperature perovskite absorber processing. Nevertheless, the crystallization pathways and mechanisms of perovskite formation involved in MASCN additive processing are far from clear. Using in situ X-ray diffraction and photoluminescence, we investigate the crystallization pathways of MAPbI3 and reveal the mechanisms of additive-assisted perovskite formation during spin coating and subsequent N2 drying. We confirm that MASCN induces large precursor aggregates in solution and, during spin coating, promotes the formation of the perovskite phase with lower nucleation density and overall larger initial nuclei size, which forms upon reaching supersaturation in solution, in addition to intermediate solvent-complex phases. Finally, during the subsequent N2 drying, MASCN facilitates the dissociation of these precursor aggregates and the solvate phases, leading to further growth of the perovskite crystals. Our results show that the nature of the intermediate phases and their formation/dissociation kinetics determine the nucleation and growth of the perovskite phase, which subsequently impact the film microstructure. These findings provide mechanistic insights underlying room-temperature, additive-assisted perovskite processing and help guide further development of such facile room-temperature synthesis routes.