A Heavy QCD Axion model in Light of Pulsar Timing Arrays

Recently, pulsar timing array (PTA) experiments reported the observation of a stochastic gravitational wave (GW) background in the nanohertz range frequency band. We show that such signal can be originated from a cosmological first-order phase transition (PT) within a well-motivated heavy (visible) QCD axion model. Considering the Peccei-Quinn symmetry breaking at the TeV scale in the scenario, we find a supercooled PT, in the parameter space of the model, prolonging the PT with the reheating temperature at the GeV scale.Comment: 7 pages, 4 figure

Magnesium Sulfate Effect on the Clinical Course and GCS of Patients with a Severe Diffuse Axonal Injury

Based on a number of studies, magnesium sulfate (MgSO4) given after a diffuse axonal injury has gained attention as a useful neuroprotective agent .The present study was conducted to examine if magnesium sulfate has a therapeutic efficacy and safety in patients with a severe diffuse axonal injury. Adult patients admitted within 1 hour of a closed Traumatic Brain Injury (TBI) with a severe diffuse axonal injury that met eligibility criteria were randomized into two groups. Our treatment guidelines consisted of an initial loading dose of 50 mg/kg magnesium sulfate and then 50 mg/kg QID up to 24 hours after the trauma. The outcome measures were mortality, GCS, and motor function scores which were assessed up to 2 months after the trauma. Magnesium showed a significant positive effect on GCS 2 months (P=0.03).  Among those in MgSO4 group, motor functioning score improved more than control group but this was not statistically significant (P = 0.51). At the end, we have demonstrated that administration of magnesium sulfate can have neuroprotective role following severe DAI.

Minimal Dose of Tranexamic Acid Is Effective in Reducing Blood Loss in Complex Spine Surgeries: A Randomized Double-Blind Placebo Controlled Study

Study Design A randomized double-blind placebo controlled study. Purpose In the present study, we aimed to assess the efficacy of tranexamic acid (TXA) in reducing blood loss after laminectomy and posterolateral fusion of the spine. Overview of Literature Blood loss is the most significant complication involved with surgery, especially in spinal surgery. Multilevel laminectomy and laminectomy with instrumentation (pedicle screws and rods) are complex spine surgeries and are considered as medium-risk procedures for bleeding. Recent reports have demonstrated that the use of antifibrinolytic drugs during surgery may reduce the risk of postoperative bleeding and one of the most frequently used antifibrinolytics is TXA. Methods In this randomized clinical trial, 50 patients eligible for laminectomy (for ≥2 level) with postero-lateral fusion with a pedicular screw (laminectomy and posterior spinal fusion) were randomly assigned to receive preoperative single doses of intravenous TXA (15 mg/kg) or 0.9% normal saline. Results Of the 50 patients, 30 (60%) were female and 20 (40%) were male. Between-group difference with respect to the total volume of blood loss during surgery was statistically significant. Conclusions The findings of this study suggest that TXA can reduce both intraoperative and immediate postoperative blood loss, decrease the need for packed cell transfusion, and reduce the duration of hospitalization after complex spinal surgeries. No adverse events related to the use of TXA were encountered in this study

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Interaoperative use of epidural methylprednisolone or bupivacaine for postsurgical lumbar discectomy pain relief : A randomized, placebo-controlled trial

<b>Background: </b> Many patients with lumbar disc surgery experience postoperative back and radicular pain, delaying hospital discharge and resumption of normal activity. Some surgeons have used intraoperative epidural corticosteroids and local anesthetics to decrease pain following surgery for a herniated lumbar disc. Controversies still exist regarding the benefits of these drugs. The present study was meant to compare the effects of the intraoperative administration of epidural methylprednisolone and bupivacaine with that of normal saline (placebo) in lumbar disc surgery for postoperative pain control. <b>Patients and Methods: </b>One hundred fifty patients with single level herniated nucleus pulposus (L4-L5 or L5-S1), which was refractory to 6 weeks of conservative management, were divided randomly in three groups. A standard hemipartial lamimectomy and discectomy was performed on all patients. At the end of the surgery, before the closure of fascia, 40 mg methylprednisolone with 3 mL normal saline for group 1, 2 mL bupivacaine 5&#x0025; with 2 mL normal saline for group 2 and 4 mL normal saline for group 3 were instilled onto the epidural and exposed nerve root. Postoperative back and radicular pain intensity was assessed by a visual analogue scale (VAS) before and at 24, 48, 72, and 96 hours after surgery. <b> Results: </b> There was no significant difference in back and radicular pain intensity between the three groups. <b> Conclusion: </b> Intraoperative administration of epidural methylprednisolone or bupivacaine does not relieve postoperative back and radicular pain

Autopsy Findings of Brainstem in Head Trauma in Comparison with CT Scan Findings in Brain Trauma Ward in Tabriz, Iran

Computed tomography (CT) is now the primary diagnostic method for head trauma because of its ability to demonstrate the nature, extent, sites, and multiplicity of brain injuries. Although there have been numerous reports on the CT findings of most types of intracranial injury, the findings in brainstem injury have not been well described. This study aimed at comparing the autopsy findings of brainstem in head trauma in comparison with CT scan results. Two hundred patients with head trauma, who expired after a period of time of hospitalization, were assessed in a diagnostic value study. Brain stem involvement was determined by autopsy as well as CT scanning of the brain during their hospitalization. The results of the two methods were compared with each other, emphasizing on the type and location of probable lesions in the brain stem. Considering the autopsy as the method of the choice, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CT scan in brain stem lesions of patients with head trauma were calculated. The effect of primary cause of head trauma, survival time and Glasgow Coma Scale (GCS) were evaluated, as well. Brain stem lesions were detected in 39 (19.5%) patients in autopsy. However, CT scan revealed brain stem lesions in 23(11.5%) cases. The sensitivity, specificity, PPV and NPV of CT scan was 59%, 100%, 100% and 91% respectively. The most common lesions of the brain stem region were as contusion of pons (8.5%), medulla (5%) and midbrain (4.5%). There were 6 (3%) cases of ponto-medullary junction tearing and 1 (0.5%) case of cervico-medullary junction tearing. CT scan is a specific method of evaluating patients with probable brain stem injuries after head trauma, but low sensitivity limits its efficacy. Our results are in conformity with the reports in the literature

Probing virtual axion-like particles by precision phase measurements

We propose an experiment for detecting Axion-Like Particles (ALPs) based on the axion-photon interaction in the presence of a non-uniform magnetic field. The impact of virtual ALPs on the polarization of the photons inside a cavity is studied and a detection scheme is proposed. We find that the cavity normal modes are dispersed differently owing to their coupling to the ALPs in the presence of a background magnetic field. This birefringence, in turn, can be observed as a phase difference between the cavity polarization modes. The signal is considerably enhanced for a squeezed light source. We argue that the amplified signal allows for exclusion of a range of axion mass 6 x 10(-4) eV less than or similar to m(a) less than or similar to 6 x 10(-3) eV even at very small axion-photon coupling constant with the potential to reach sensitivity to the QCD axion. Our scheme allows for the exclusion of a range of axion masses that has not yet been covered by other experimental techniques

Endovascular Treatment of Intracranial Artery Dissection: Clinical and Angiographic Follow-Up

Background. Intracranial artery dissections are rare and many controversies exist about treatment options. The aim of this study was to evaluate the efficacy and safety of the endovascular approach in patients with an intracranial dissection presenting with different symptoms. Methods. We prospectively evaluated the clinical features and treatment outcomes of 30 patients who had angiographically confirmed nontraumatic intracranial dissections over 4 years. Patients were followed up for 17 months, and their final outcomes were assessed by the modified Rankin Score (mRS) and angiography. Results. Sixteen (53.3%) patients had a dissection of the anterior circulation, whereas 14 (46.7%) had a posterior circulation dissection. Overall, 83.3% of the patients suffered a subarachnoid hemorrhage (SAH). Grade IV Hunt and Hess score was seen in 32% of the SAH presenting cases. Parent artery occlusion (PAO) with coil embolization was used in 70% of the cases. The prevalence of overall procedural complications was 23.3%, and all were completely resolved at the end of follow-up. No evidence of in-stent occlusion/stenosis or rebleeding was observed in our cases during follow-up. Angiography results improved more frequently in the PAO with coil embolization group (100%) than in the stent-only-treated group (88.9%) (P=0.310) and the unruptured dissection group (5/5, 100%) in comparison with the group that presented with SAH (95.8%) (P=0.833). Conclusion. Favorable outcomes were achieved following an endovascular approach for symptomatic ruptured or unruptured dissecting aneurysms. However, the long-term efficacy and durability of these procedures remain to be determined in a larger series