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The identification of lattice multiphases in TiO2 nanocrystals is studied by high resolution transmission electron microscope and electron diffraction patterns. Based on the spectroscopic analysis using soft x-ray absorption and resonant inelastic soft x-ray scattering, it is believed that the oxygen vacancies at the interface exhibit structural distortion of the TiO68−cluster around the defect site as for the multiphase lattice. We elucidate that the extra 3d electrons nearby induce the inelastic scattering features with the excitation energy dependence owing to different energy relaxation processes, a characteristic of the electron-phonon coupling or the nature of the electron-hole pair at the intermediate state. The manifold dd excitations driven by the strong interaction between Ti-3d and O-2p electrons are noticeably rich, coexisting on both Ti and O sites. This sophisticated experiment can advance the perspective of nanocomposite TiO2 for various interactions of surface Ti3+ in applications of future devices.

Owais Gul,1 Maria Khalid,1 Saqib Gul2 1Department of Internal Medicine, United Health Services Wilson Medical Center, Johnson City, NY, USA; 2Department of Medicine, Hamdard University, Karachi, PakistanCorrespondence: Owais Gul Department of Internal Medicine, United Health Services Wilson Medical Center, NY, USA, Tel +1 (607)-429-8737, Email owaisgul96@yahoo.com

Sumaira Gul,1 Inayat Ur Rehman,1 Khang Wen Goh,2 Zahid Ali,3 Aziz Ur Rahman,4 Asad Khalil,5 Ismail Shah,6 Tahir Mehmood Khan,6 Long Chiau Ming7,8 1Department of Pharmacy, Garden Campus, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan; 2Faculty of Data Science and Information Technology, INTI International University, Nilai, Malaysia; 3Department of Pharmacy, University of Peshawar, Peshawar, Pakistan; 4Department of Urology, North West General Hospital and Research Center Peshawar, Peshawar, Pakistan; 5Department of Medicine, Lady Reading Hospital, Peshawar, Pakistan; 6Institute of Pharmaceutical Sciences, University of Veterinary and Animal Sciences Lahore, Lahore, Pakistan; 7PAP Rashidah Sa’adatul Bolkiah Institute of Health Sciences, Universiti Brunei Darussalam, Gadong, Brunei Darussalam; 8School of Medical and Life Sciences, Sunway University, Sunway City, MalaysiaCorrespondence: Inayat Ur Rehman, Department of Pharmacy, Garden Campus, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, 23200, Pakistan, Email Inayat.rehman@awkum.edu.pk Long Chiau Ming, School of Medical and Life Sciences, Sunway University, Sunway City, Selangor, 47500, Malaysia, Email chiaumingl@sunway.edu.myIntroduction: Asthma is one of the common major non-communicable respiratory diseases, and is associated with a lower health-related quality of life (QOL). Poor inhalation is a significant contributing factor to poor control of asthma. Community pharmacist has a vital role to play in assisting patients and ultimately improving their asthma conditions through the use of inhalers.Aim: This study aimed to assess the effectiveness of “pre” and “post” educational intervention by a community pharmacist within a community pharmacy on asthma patients’ QOL, inhaler technique, and adherence to therapy during the endemic phase of COVID-19.Methods: A “pre” and “post” interventional study was performed at a community pharmacy in the city of Mardan, Pakistan, in 2022 during the COVID-19 pandemic. Patients were divided into two groups, ie control and pharmacist-led education groups. After assigning patients to both groups, the baseline data were collected and followed for one month to compare the reduction in errors in the use of inhalers, QOL, and adherence to therapy. A paired sample t-test was performed, keeping a p-value < 0.05 as statistical significance.Results: A total of 60 patients were recruited, majority (58.3%) were females, and 28.3% were from the age group of 46– 55 years old. A statistically significant difference was observed in the pre- and post-education QOL score among patients in the pharmacist-led education group, from a mean ± SD at pre-education of 40.23± 10.03 to a mean±SD at post-education of 48.10± 5.68. Similarly, a statistically significant difference was observed for the correct use of inhalers, ie MDIs and DPIs. Similarly, a statistically significant difference was observed in the adherence status between pre-education and post-education by pharmacists.Conclusion: The findings of the study revealed a positive impact of community pharmacist-led education on QOL, inhaler technique, and adherence to therapy among patients with asthma.Keywords: adherence, asthma, community pharmacist, pharmacist-led education, quality of life, Pakistan

This contribution describes the indirect electrochemical oxidation of wastewater laden with bromothymol blue and methyl red dyes using a laboratory-scale electrochemical reactor with a Ti/Ru0.3Ti0.7O2 anode and stainless-steel cathode. The influence of current density, pH, and electrolyte concentrations on the oxidative degradation pattern of the dyes in the wastewater was also investigated by coupling the electrochemical reactor with an Ultraviolet–Visible spectrometer. By indirect oxidation, 97% of the bromothymol blue at 10 mA cm–2 current density and pH 3.0 and 98% of the methyl red at 2 mA cm–2 current density at pH 3.0 were indirectly oxidized in 10 min Initial concentrations of each were 200 ppm. During the degradation of the dyes, electrochemically generated chlorine and hypochlorite ions (OCl)– played pivotal roles. Under the aforementioned ideal circumstances, the minimum energy consumption values for bromothymol blue and methyl red were 0.2025 and 0.0636 kW h m–3, respectively. The anode exhibited an excellent service life for treating dye wastewater, and repeated tests and surface analysis revealed no evident passivation. In this way, a variety of dyes in effluents can be cheaply degraded by electrolyzing with a Ti/Ru0.3Ti0.7O2 anode, utilizing readily available electrolytes and with minimal electricity requirements. [ABSTRACT FROM AUTHOR]

Electrocatalysis of the oxygen evolution reaction is central to several energy technologies including electrolyzers, solar fuel generators, and air-breathing batteries. Strong acid electrolytes are desirable for many implementations of these technologies, although the deployment of such device designs is often hampered by the lack of non-precious-metal oxygen evolution electrocatalysts, with Ir-based oxides comprising the only known catalysts that exhibit stable activity at low overpotential. During our exploration of the Mn-Sb-O system for precious-metal-free electrocatalysts, we discovered that Mn can be incorporated into the rutile oxide structure at much higher concentrations than previously known, and that these Mn-rich rutile alloys exhibit great catalytic activity with current densities exceeding 50 mA cm-2 at 0.58 V overpotential and catalysis onset at 0.3 V overpotential. While this activity does not surpass that of IrO2, Pourbaix analysis reveals that the Mn-Sb rutile oxide alloys have the same or better thermodynamic stability under operational conditions. By combining combinatorial composition, structure, and activity mapping with synchrotron X-ray absorption measurements and first-principles materials chemistry calculations, we provide a comprehensive understanding of these oxide alloys and identify the critical role of Sb in stabilizing the trivalent Mn octahedra that have been shown to be effective oxygen evolution reaction (OER) catalysts.

Establishing catalytic structure-function relationships introduces the ability to optimize the catalyst structure for enhanced activity, selectivity, and durability against reaction conditions and prolonged catalysis. Here we present experimental and computational data elucidating the mechanism for the O2 reduction reaction with a conductive nickel-based metal-organic framework (MOF). Elucidation of the O2 reduction electrokinetics, understanding the role of the extended MOF structure in providing catalytic activity, observation of how the redox activity and pKa of the organic ligand influences catalysis, and identification of the catalyst active site yield a detailed O2 reduction mechanism where the ligand, rather than the metal, plays a central role. More generally, familiarization with how the structural and electronic properties of the MOF influence reactivity may provide deeper insight into the mechanisms by which less structurally defined nonplatinum group metal electrocatalysts reduce O2.

We combine high-energy resolution fluorescence detection (HERFD) X-ray absorption spectroscopy (XAS) measurements with first-principles density functional theory (DFT) calculations to provide a molecular-scale understanding of local structure, and its role in defining optoelectronic properties, in CH3NH3Pb(I1-xBrx)3 perovskites. The spectra probe a ligand field splitting in the unoccupied d states of the material, which lie well above the conduction band minimum and display high sensitivity to halide identity, Pb-halide bond length, and Pb-halide octahedral tilting, especially for apical halide sites. The spectra are also sensitive to the organic cation. We find that the halides in these mixed compositions are randomly distributed, rather than having preferred octahedral sites, and that thermal tilting motions dominate over any preferred structural distortions as a function of halide composition. These findings demonstrate the utility of the combined HERFD XAS and DFT approach for determining structural details in these materials and connecting them to optoelectronic properties observed by other characterization methods.

The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting X-ray diffraction data and X-ray emission spectra, using an energy dispersive spectrometer, at ambient conditions, and used this approach to study the room temperature structure and intermediate states of the photosynthetic water oxidizing metallo-protein, photosystem II. Moreover, we have also used this setup to simultaneously collect the X-ray emission spectra from multiple metals to follow the ultrafast dynamics of light-induced charge transfer between multiple metal sites. A Mn-Ti containing system was studied at an XFEL to demonstrate the efficacy and potential of this method.

First principles calculations in the context of density functional theory (DFT) provides a platform to investigate the material's properties in a way to explain the physics of solids. Electronic, structural, and optical properties for pure and Cu-doped LaAl[O.sub.3] are investigated. The study reveals that the band structure of LaAl[O.sub.3] after the inclusion of Cu at the La site is affected significantly. Due to the substitution of Cu, there is a decrease in the band gap from 3.02 eV to 2.95 eV. Furthermore, the partial density of states of LaAl[O.sub.3] changes significantly after Cu doping, which has confirmed the doping effect on intrinsic LaAl[O.sub.3]. The p and d states play a vital role on top of the valence band. The range in which the top of a valence band lies is from 0 eV to -9 eV having a significant effect and it is because of Cu-d states. The optical properties of both pure and doped systems were analyzed. Redshift was observed as absorption edge shifted from 4.5 eV to 4.0 eV and even the refractive index reduces from 2.25 to 1.0, which means the Cu inclusion significantly play its role to tailor optical properties. Hence Cu-doping affects the properties of LaAl[O.sub.3] and makes it a suitable candidate for use in different optical devices. Key words: doping, density functional theory, and gap, density of states, optical properties, refractive index. Des calculs bases sur les principes premiers, dans le cadre de la theorie de la fonctionnelle de densite (TFD/DFT), nous fournissent une plateforme pour examiner les proprietes des materiaux en physique du solide. Nous analysons les proprietes electroniques, structurelles et optiques du LaAl[O.sub.3] pur et dope au Cu. L'etude revele que la structure de bande du LaAl[O.sub.3] est affectee de facon significative apres l'inclusion de Cu sur les sites de La. Suite a cette substitution, la bande interdite (gap) est diminuee de 3.02 eV a 2.95 eV. De plus, la densite partielle d'etats (DPE/PDOS) du LaAl[O.sub.3] change de facon marquee apres le dopage au Cu, ce qui confirme l'effet du dopage sur le LaAl[O.sub.3]. Les etats p et d jouent un role crucial sur le haut de la bande de valence. Le domaine dans lequel se trouve le haut de la bande de valence se situe entre 0 eV et -9 eV, un effet significatif cause par les etats d du Cu. Nous analysons les proprietes optiques des systemes purs et dopes. Un decalage vers le rouge est observe suite au deplacement du seuil d'absorption de 4.5 eV a 4.0 eV et meme l'indice de refraction est reduit de 2.25 a 1.0, ce qui signifie que l'inclusion du Cu joue son role pour ajuster les proprietes optiques. Par consequent, les effets du dopage par le Cu affectent les proprietes du LaAl[O.sub.3] et en font un bon candidat pour utilisation dans les dispositifs optiques. [Traduit par la Redaction] Mots-cles : dopage, theorie de la fonctionnelle de densite, bande interdite, densite d'etats, proprietes optiques, indice de refraction., 1. Introduction The power and energy crises demand that humans establish new ideas and perceptions; therefore different theoretical and experimental methods in research have been developed in the materials field. [...]

The design of active, robust, and nonprecious electrocatalysts with both H2 and O2 evolution reaction (HER and OER) activities for overall water splitting is highly desirable but remains a grand challenge. Herein, we report a facile two-step method to synthesize porous Co-P/NC nanopolyhedrons composed of CoPx (a mixture of CoP and Co2P) nanoparticles embedded in N-doped carbon matrices as electrocatalysts for overall water splitting. The Co-P/NC catalysts were prepared by direct carbonization of Co-based zeolitic imidazolate framework (ZIF-67) followed by phosphidation. Benefiting from the large specific surface area, controllable pore texture, and high nitrogen content of ZIF (a subclass of metal-organic frameworks), the optimal Co-P/NC showed high specific surface area of 183 m2 g-1 and large mesopores, and exhibited remarkable catalytic performance for both HER and OER in 1.0 M KOH, affording a current density of 10 mA cm-2 at low overpotentials of -154 mV for HER and 319 mV for OER, respectively. Furthermore, a Co-P/NC-based alkaline electrolyzer approached 165 mA cm-2 at 2.0 V, superior to that of Pt/IrO2 couple, along with strong stability. Various characterization techniques including X-ray absorption spectroscopy (XAS) revealed that the superior activity and strong stability of Co-P/NC originated from its 3D interconnected mesoporosity with high specific surface area, high conductivity, and synergistic effect of CoPx encapsulated within N-doped carbon matrices.

Monoclinic scheelite bismuth vanadate (m-BiVO4) is a promising semiconductor photoanode for photoelectrochemical (PEC) water splitting. Despite considerable recent progress in achieving improved photocurrents and photovoltages, there remain open questions about the basic optoelectronic properties of this material. Indeed, there is disagreement about the nature of its fundamental bandgap, with theoretical predictions and some experimental observations pointing to an indirect bandgap and other experimental studies to a direct bandgap. Knowledge of this property is critical for understanding light absorption and photocarrier properties, as well as for establishing rational approaches to improved efficiency. Here, experimental spectroscopic techniques are used to resolve this issue and provide a fundamental portrait of the optical properties of the material. Resonant inelastic X-ray scattering proves conclusively that m-BiVO4 is an indirect bandgap semiconductor. These measurements are supported by UV-vis absorption spectroscopy and spectroscopic ellipsometry, which confirm this finding and also indicate the presence of a direct transition located at 200 meV above the indirect one. The spectral dependence of the optical constants is determined by development of a photophysical model for the ellipsometric data. Photogenerated carrier dynamics are probed by transient absorption spectroscopy, which reveals a relatively long lifetime compared to other commonly utilized metal oxide photoanodes and is attributed to the indirect nature of the fundamental gap. The combination of strong visible light absorption and relatively long excited state lifetime provides the basis for the high performance that has been achieved from BiVO4 photoanodes for water splitting.

A comprehensive approach to understanding the electronic structure of monoclinic scheelite bismuth vanadate (ms-BiVO4), including both valence band (VB) and conduction band (CB) orbital character, is presented. Density functional theory (DFT) calculations are directly compared to experimental data obtained via X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy, resonant inelastic X-ray spectroscopy (RIXS), and X-ray photoelectron spectroscopy to provide a complete portrait of the total and partial density of states (DOS) near the bandgap. DFT calculations are presented to confirm the VB maximum and CB minimum are comprised primarily of O 2p and V 3d orbitals, respectively. Predicted triplet d-manifold splitting of V 3d CB states, arising from lone pair-induced lattice distortions, is quantified by V L-and O K-edge XAS. Furthermore, the partial contributions to the total DOS within both the CB and VB, determined by RIXS, are found to be in excellent agreement with DFT calculations. Energy levels are placed relative to the vacuum level by photoemission spectroscopy, which provides a measure of the work function and electron affinity of the investigated BiVO4 thin film. The implications of the fundamental electronic structure of ms-BiVO4 on its photocatalytic behavior, as well as considerations for improvements by substitutional incorporation of additional elements, are discussed.

Owais Gul,1 Saqib Gul,2 Abdul Aziz Godil3 1Department of Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan; 2Department of Medicine, Hamdard University, Karachi, Pakistan; 3Department of Medicine, Jinnah Medical and Dental College, Karachi, PakistanWe read with great interest the recently published article “Atrial natriuretic peptide and posterior pituitary neurohormone changes in patients with acute schizophrenia” by Guzel et al.1 The study results are vital in understanding the variations among the levels of posterior pituitary neurohormones in patients with acute schizophrenia and seem to be of great value for future therapeutic modifications of the disease.View the original paper by Guzel and colleagues.

BackgroundClustering analysis of microarray data is often criticized for giving ambiguous results because of sensitivity to data perturbation or clustering techniques used. In this paper, we describe a new method based on principal component analysis and ensemble consensus clustering that avoids these problems.ResultsWe illustrate the method on a public microarray dataset from 36 breast cancer patients of whom 31 were diagnosed with at least two of three pathological stages of disease (atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC). Our method identifies an optimum set of genes and divides the samples into stable clusters which correlate with clinical classification into Luminal, Basal-like and Her2+ subtypes. Our analysis reveals a hierarchical portrait of breast cancer progression and identifies genes and pathways for each stage, grade and subtype. An intriguing observation is that the disease phenotype is distinguishable in ADH and progresses along distinct pathways for each subtype. The genetic signature for disease heterogeneity across subtypes is greater than the heterogeneity of progression from DCIS to IDC within a subtype, suggesting that the disease subtypes have distinct progression pathways. Our method identifies six disease subtype and one normal clusters. The first split separates the normal samples from the cancer samples. Next, the cancer cluster splits into low grade (pathological grades 1 and 2) and high grade (pathological grades 2 and 3) while the normal cluster is unchanged. Further, the low grade cluster splits into two subclusters and the high grade cluster into four. The final six disease clusters are mapped into one Luminal A, three Luminal B, one Basal-like and one Her2+.ConclusionWe confirm that the cancer phenotype can be identified in early stage because the genes altered in this stage progressively alter further as the disease progresses through DCIS into IDC. We identify six subtypes of disease which have distinct genetic signatures and remain separated in the clustering hierarchy. Our findings suggest that the heterogeneity of disease across subtypes is higher than the heterogeneity of the disease progression within a subtype, indicating that the subtypes are in fact distinct diseases.

Exercise is essential for mastering mathematics, but it faces two major hurdles. First, students are often not motivated to do their homework. Second, checking traditional homework is a manual and labor-intensive process that becomes harder to support as the number of students increases. We argue that computer games could alleviate both problems. In contrast to homework, students are willing to spend many hours playing video games. And because video games keep track of the gamers' performance, they offer a scalable solution to the problem of checking the homework. We describe an experiment to augment traditional homework with a computer game that we have developed for exercising the topics of symmetry groups in an undergraduate college course. We describe the mathematical background of the subject matter, how we have embedded the mathematics into the game, the empirical results of playing the game, and the insights we have gained from this experiment. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to elucidate the possible effects of the acute/long-term infusion of glucagon in the brain as the regulatory role on the endocrine secretions of the pancreas. MATERIALS AND METHODS: Ninety male Wistar albino rats were divided as Control, artificial Cerebrospinal Fluid (aCSF) (120 min), Glucagon (120 min), pancreatic denervation (PD)+aCSF (120 min), PD+Glucagon (120 min), aCSF (7 days), Glucagon (7 days), PD+aCSF (7 days) and PD+Glucagon (7 days). Glucagon and solvent (aCSF) were administered after pancreatic denervation (PD) by Hamilton syringe and osmotic mini pump (1 µg/10 µl/min) in the third ventricle of the brain. RESULTS: Acute intracerebroventricular (icv) administration of glucagon resulted in an elevation of glucagon levels and a concurrent reduction in blood glucose levels. Furthermore, in both the PD+aCSF (7 days) and PD+Glucagon (7 days) groups, there was a notable decrease in propiomelanocortin (POMC) and agouti-related protein (AgRP). Significant changes were observed in feed consumption and body weight, as well as pancreatic glucagon levels, with a simultaneous decrease in insulin levels in the PD (7 days), Glucagon (7 days), and PD+Glucagon (7 days) groups. These alterations were statistically significant when compared to the control group (p<0.05). CONCLUSIONS: The research outcomes established that pancreas-secreted glucagon functions as a neurohormone within the brain, activating central pathways linked to blood glucose regulation. The presence of glucagon led to a decrease in POMC levels. Surprisingly, this reduction in POMC resulted in the suppression of AgRP. Contrary to expectations, the suppression of AgRP led to an increase in food intake rather than a decrease. As already highlighted in the results section, it was emphasized that POMC may play a more significant role than AgRP in influencing feeding behavior. [ABSTRACT FROM AUTHOR]