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Antibiotics (ABs) have saved countless lives, but their misuse has led to a serious problem: antibiotic resistance. This growing phenomenon poses serious threats to public health worldwide, as it could make treating infections significantly more difficult in the future. This study aimed to investigate antibiotic consumption and use patterns in a tertiary hospital in Sana'a, Yemen, by comparing Prescribed Daily Doses (PDD) to Defined Daily Doses (DDD), and identifying factors associated with antibiotic misuse and its impact on patient outcomes. A prospective cross-sectional study was conducted among adult inpatients in a tertiary hospital in Sana'a, Yemen over two months (January 12 to March 11, 2024), involving 597 patients. Data on antibiotic prescriptions, patient demographics, and outcomes were collected. A high prevalence of antibiotic use was observed (92.5%), with a notable proportion of prescriptions from the \"Watch\" category (56.7%). Significant PDD-DDD deviations were common, encompassing both overuse (36.8%) and underuse (63.2%). Factors associated with antibiotic deviations included patient age (26-44 years), gender (female), and ward type (private). The most commonly prescribed antibiotics were Ceftriaxone (33.6%), Metronidazole (21.8%), Vancomycin (6.0%), Levofloxacin (4.9%), Imipenem/Cilastatin (4.7%), and Moxifloxacin (3.6%). Notable deviations from DDD were observed for Levofloxacin (overuse by 28%), Imipenem/Cilastatin (underuse by 40.5%), and other agents. Antibiotic misuse was associated with longer hospital stays and less favorable discharge outcomes. The study found an alarmingly high prevalence of antibiotic use and excessive consumption, with both overuse and underuse patterns observed, underscoring the need for effective regulatory interventions and improved antibiotic stewardship in Yemen.

Background and Objectives: Polycystic ovarian syndrome (PCOS) is a widespread endocrine disorder affecting 5–18% of females in their childbearing age. The aim of this study is to assess the efficacy of combining a low dosage of human chorionic gonadotropin (HCG) along with clomiphene citrate (CC) for stimulating ovulation in infertile women diagnosed with CC-resistant PCOS. Materials and Methods: A randomized controlled trial was carried out on 300 infertile CC-resistant PCOS women. All participants were assigned to two groups: the CC-HCG group and the CC-Placebo group. Subjects in the CC-HCG group were given CC (150 mg/day for 5 days starting on the 2nd day of the cycle) and HCG (200 IU/day SC starting on the 7th day of the cycle). Subjects in the CC-Placebo group were given CC and a placebo. The number of ovarian follicles > 18 mm, cycle cancellation rate, endometrial thickness, ovulation rate, clinical pregnancy rate, and occurrence of early ovarian hyper-stimulation syndrome were all outcome variables in the primary research. Results: Data from 138 individuals in the CC-HCG group and 131 participants in the CC-Placebo group were subjected to final analysis. In comparison to the CC-Placebo group, the cycle cancellation rate in the CC-HCG group was considerably lower. The CC-HCG group exhibited a substantial increase in ovarian follicles reaching > 18 mm, endometrial thickness, and ovulation rate. The clinical pregnancy rate was higher in the CC-HCG group (7.2% vs. 2.3%; CC-HCG vs. CC-Placebo). Upon adjusting for BMI and age, the findings of our study revealed that individuals in the CC-HCG group who had serum prolactin levels below 20 (ng/mL), secondary infertility, infertility duration less than 4 years, baseline LH/FSH ratios below 1.5, and serum AMH levels more than 4 (ng/mL) had a higher likelihood of achieving pregnancy. In the CC-Placebo group, there was a greater prediction of clinical pregnancy for those with serum AMH (<4), primary infertility, serum prolactin ≤ 20 (ng/mL), baseline LH/FSH < 1.5, and infertility duration < 4 years. Conclusions: The use of a small dose of HCG along with CC appeared to be an effective treatment in reducing cycle cancelation, improving the clinical pregnancy rate and ovulation rate in CC-resistant PCOS patients. The trial was registered with Clinical Trials.gov, identifier NCT02436226

Background and Objectives: One of the most widely used reversible contraceptive techniques among women of reproductive age worldwide is oral contraceptives (OCPs). Despite their widespread use, OCPs are associated with increased risks of stroke, yet the extent of awareness of these risks among women remains insufficiently explored. This study aims to evaluate the level of awareness among women resident in Saudi Arabia regarding the potential risk of stroke linked to the use of OCPs. Materials and Methods: A cross-sectional descriptive study was conducted targeting women of reproductive age (18–49 years). Data was collected through an online self-administrated questionnaire distributed via social media platforms, encompassing sociodemographic characteristics, OCP usage patterns, and awareness of stroke risks, perceived side effects of OCPs, symptoms of stroke, and methods to reduce stroke incidence. Statistical analysis was performed using SPSS version 23, with descriptive statistics for categorical data and chi-square tests to assess associations. Results: A total of 516 women participated in the study. Of these, 148, or over a quarter (28.7%), of the participants reported using oral contraceptive pills; 86, or more than half (58%), who use OCPs are not sure what type of OCPs they use; 60, or over half of the participants (40.5%), have been using for less than a year. Over two thirds of the participants (350, 67.8%) are not aware that using OCP increases the risk of stroke. The most recognized side effect of OCPs use was weight gain (38.2%), while awareness of stroke as a side effect was significantly lower (24.6%). Additionally, 62.8% of respondents identified selecting the appropriate type of contraceptive as the best way to prevent stroke while taking OCPs. Conclusions: this study highlights the need for increased awareness and education about the potential risk of cerebral thrombosis associated with OCP use among Saudi women. Addressing this knowledge gap through targeted educational initiatives could help mitigate the risks and improve overall public health outcomes.

Strain-free GaAs cone-shell quantum dots have a unique shape, which allows a wide tunability of the charge-carrier probability densities by external electric and magnetic fields. Here, the influence of a lateral electric field on the optical emission is studied experimentally using simulations. The simulations predict that the electron and hole form a lateral dipole when subjected to a lateral electric field. To evaluate this prediction experimentally, we integrate the dots in a lateral gate geometry and measure the Stark-shift of the exciton energy, the exciton intensity, the radiative lifetime, and the fine-structure splitting (FSS) using single-dot photoluminescence spectroscopy. The respective gate voltage dependencies show nontrivial trends with three pronounced regimes. We assume that the respective dominant processes are charge-carrier deformation at a low gate voltage U, a vertical charge-carrier shift at medium U, and a lateral charge-carrier polarization at high U. The lateral polarization forms a dipole, which can either enhance or compensate the intrinsic FSS induced by the QD shape anisotropy, dependent on the in-plane orientation of the electric field. Furthermore, the data show that the biexciton peak can be suppressed by a lateral gate voltage, and we assume the presence of an additional vertical electric field induced by surface charges.

Letrozole, an aromatase inhibitor, has recently been introduced as the preferred treatment option for ectopic pregnancy. To date, no study has investigated the effect of letrozole alone on placental tissue. The present study aimed to evaluate the effect of different doses of letrozole on the placenta of rats and to clarify the underlying mechanism. Sixty pregnant female rats were equally divided into three groups, namely the control group (GI), low-dose (0.5 mg/Kg/day) letrozole group (GII), which is equivalent to the human daily dose (HED) of 5 mg, and high-dose (1 mg/Kg/day) letrozole group (GIII), equivalent to the HED of 10 mg. Letrozole was administered by oral gavage daily from day 6 to 16 of gestation. Data were analyzed using a one-way analysis of variance followed by Tukey's test and Chi square test. P<0.05 was considered statistically significant. Compared to the GI and GII groups, high-dose letrozole significantly increased embryonic mortality with a high post-implantation loss rate (P<0.001) and significantly reduced the number of viable fetuses (P<0.001) and placental weight (P<0.001) of pregnant rats. Moreover, it significantly reduced placental estrogen receptor (ER) and progesterone receptor (PR) (P<0.001) and the expression of vascular endothelial growth factor (P<0.001), while increasing the apoptotic index of cleaved caspase-3 (P<0.001). Letrozole inhibited the expression of ER and PR in rat placenta. It interrupted stimulatory vascular signals causing significant apoptosis and placental vascular dysfunction. Letrozole in an equivalent human daily dose of 10 mg caused a high post-implantation loss rate without imposing severe side effects.

The first part of this work evaluates Al-doped ZnO (AZO) as an optically transparent top-gate material for studies on semiconductor quantum dots. In comparison with conventional Ti gates, samples with AZO gates demonstrate a more than three times higher intensity in the quantum dot emission under comparable excitation conditions. On the other hand, charges inside a process-induced oxide layer at the interface to the semiconductor cause artifacts at gate voltages above U≈ 1 V. The second part describes an optical and simulation study of a vertical electric-field (F)-induced switching from a strong to an asymmetric strong–weak confinement in GaAs cone-shell quantum dots (CSQDs), where the charge carrier probability densities are localized on the surface of a cone. These experiments are performed at low U and show no indications of an influence of interface charges. For a large F, the measured radiative lifetimes are substantially shorter compared with simulation results. We attribute this discrepancy to an F-induced transformation of the shape of the hole probability density. In detail, an increasing F pushes the hole into the wing part of a CSQD, where it forms a quantum ring. Accordingly, the confinement of the hole is changed from strong, which is assumed in the simulations, to weak, where the local radius is larger than the bulk exciton Bohr radius. In contrast to the hole, an increasing F pushes the electron into the CSQD tip, where it remains in a strong confinement. This means the radiative lifetime for large F is given by an asymmetric confinement with a strongly confined electron and a hole in a weak confinement. To our knowledge, this asymmetric strong–weak confinement represents a novel kind of quantum mechanical confinement and has not been observed so far. Furthermore, the observed weak confinement for the hole represents a confirmation of the theoretically predicted transformation of the hole probability density from a quantum dot into a quantum ring. For such quantum rings, application as storage for photo-excited charge carriers is predicted, which can be interesting for future quantum photonic integrated circuits.

Hyperemesis gravidarum (HG) is a condition that develops early in pregnancy, before 16 weeks of gestation, and is characterized by severe nausea and/or vomiting, inability to tolerate food and/or beverages, and substantial impairment of daily activities. Hyperemesis gravidarum can have obvious maternal and fetal consequences. This study aimed to assess the prevalence of HG, investigate its associated electrolyte and hematologic disturbances, and identify risk factors among pregnant women in Aljouf, Saudi Arabia. A retrospective observational case-control study was conducted using 200 medical records selected from a total of 9,090 records of pregnant women at the Maternity and Children Hospital in Aljouf, covering the period from November 2020 to November 2023. The prevalence of hyperemesis gravidarum was 1.1% among the studied pregnant women. Patients diagnosed with hyperemesis gravidarum showed significantly lower body weight and BMI than controls. Nearly 48% of HG cases occurred in women aged 30-39 years, while 52% were in the first trimester. Furthermore, 36% of the affected women were primigravida, and 11% were pregnant with twins. Hypotension was observed in 35% of HG cases. Hyponatremia occurred in 29% of patients, hypokalemia in 21%, and hypochloremia in 24%. Hematological disturbances included increased Hb levels in 11% of cases, increased hematocrit in 12%, leukocytosis in 19%, and neutrophilia in 17% of the patients. Hypotension, electrolyte imbalance, and hematological disturbances are the primary consequences of HG. First-trimester pregnancy and low gestational age are the most important risk factors for HG. Strategies by healthcare centers and further research are needed to enhance the treatment, management, and prevention methods of HG.

The temperature-dependent intensities of the exciton (X) and biexciton (XX) peaks from single GaAs cone–shell quantum dots (QDs) are studied with micro photoluminescence (PL) at varied excitation power and QD size. The QDs are fabricated by filling self-assembled nanoholes, which are drilled in an AlGaAs barrier by local droplet etching (LDE) during molecular beam epitaxy (MBE). This method allows the fabrication of strain-free QDs with sizes precisely controlled by the amount of material deposited for hole filling. Starting from the base temperature T = 3.2 K of the cryostat, single-dot PL measurements demonstrate a strong enhancement of the exciton emission up to a factor of five with increasing T. Both the maximum exciton intensity and the temperature Tx,max of the maximum intensity depend on excitation power and dot size. At an elevated excitation power, Tx,max becomes larger than 30 K. This allows an operation using an inexpensive and compact Stirling cryocooler. Above Tx,max, the exciton intensity decreases strongly until it disappears. The experimental data are quantitatively reproduced by a model which considers the competing processes of exciton generation, annihilation, and recombination. Exciton generation in the QDs is achieved by the sum of direct excitation in the dot, plus additional bulk excitons diffusing from the barrier layers into the dot. The thermally driven bulk-exciton diffusion from the barriers causes the temperature enhancement of the exciton emission. Above Tx,max, the intensity decreases due to exciton annihilation processes. In comparison to the exciton, the biexciton intensity shows only very weak enhancement, which is attributed to more efficient annihilation processes.

Site-controlled Ga droplets on AlGaAs substrates are fabricated using area-selective deposition of Ga through apertures in a mask during molecular beam epitaxy (MBE). The Ga droplets can be crystallized into GaAs quantum dots using a crystallization step under As flux. In order to model the complex process, including the masked deposition of the droplets and a reduction of their number during a thermal annealing step, a multiscale kinetic Monte Carlo (mkMC) simulation of self-assembled Ga droplet formation on AlGaAs is expanded for area-selective deposition. The simulation has only two free model parameters: the activation energy for surface diffusion and the activation energy for thermal escape of adatoms from a droplet. Simulated droplet numbers within the opening of the aperture agree quantitatively with the experimental results down to the perfect site-control, with one droplet per aperture. However, the model parameters are different compared to those of the self-assembled droplet growth. We attribute this to the presence of the mask in close proximity to the surface, which modifies the local process temperature and the As background. This approach also explains the dependence of the model parameters on the size of the aperture.

Surgery is the main line of treatment of endometriosis. Patients with stage IV endometriosis have more extensive adhesions, which make the surgery difficult. There are no accurate non-invasive predictive preoperative parameters of stage IV endometriosis and no consensus has been reached. In the present study, we included 150 females admitted for surgical removal of endometriosis. We scored and classified endometriosis into four stages according to the revised ASRM classification. We compared between baseline characteristics of patients with different stages of endometriosis, and then we selected the best combination of diagnostic and predictive parameters of stage IV endometriosis. Predictors of stage IV endometriosis and indicators for safety surgery were as follows: VAS [greater than or equal to] 4 (p < 0.001), fixed uterus (p = 0.005), fixed ovarian cysts (p < 0.001), tender uterosacral ligament nodule (p < 0.001), tender rectovaginal septum nodule (p = 0.003), bilateral endometriosis (p < 0.001), and sum of sizes of endometriotic nodules (p < 0.001). Fixed uterus, fixed ovarian cysts, tender uterosacral ligament nodule, tender rectovaginal septum nodule, bilateral endometriosis, and indications for surgery were significantly considered adequate predictive markers for stage IV endometriosis.