Frontal Sinus Fractures: Management at the Yalgado Ouedraogo University Hospital Centre (Burkina Faso)

Introduction: Frontal sinus fractures are potentially serious. They are defined as a solution of continuity, open or closed, of one or both bone tables of the frontal sinus. This study aims to report on the management of them at the Yalgado OUEDRAOGO University Hospital Centre. Methodology: It is a descriptive cross-sectional study with retrospective collection from January 01, 2016 to December 31, 2018. Patients with frontal sinus fractures were managed at the Yalgado OUEDRAOGO University Hospital Centre through CT-scan proof. Results: Over three years, a total of 102 cases of frontal sinus fractures were collected with 29.9 years as average age. There were 96 men. Workers in the informal sector and pupils/students represented 58.90% of patients. The residence of the patients was urban in 68.80% of cases and rural in 31.40%. Road traffic accidents (RTAs) happened in 90.20%, and involved 2-wheelers in 98.20%. None of these drivers was wearing a helmet. The type III frontal fracture of Ioannides et al. represented 51.9% of cases. In 89.21% of cases, other facial and/or cranioencephalic injuries were compounded to frontal sinus fractures. No surgical management was observed in 82 (80.39%) patients and surgical management in 20 (19.61%) patients. The outcome was favourable, but sequelae and/or complications were noted in 10 patients who had surgery and 30 patients who did not. Conclusion: These results enforce helmet wearing for all riders of two-wheeled machines. In addition, vaccinations to prevent meningitis in frontal sinus fractures with dural breach should be systematic.

Functional role of frontal electroencephalogram alpha asymmetry in the resting state in patients with depression:A review

Depression is a psychological disorder that affects the general public worldwide.It is particularly important to make an objective and accurate diagnosis of depression,and the measurement methods of brain activity have gradually received increasing attention.Resting electroencephalogram(EEG)alpha asymmetry in patients with depression shows changes in activation of the alpha frequency band of the left and right frontal cortices.In this paper,we review the findings of the relationship between frontal EEG alpha asymmetry in the resting state and depression.Based on worldwide studies,we found the following:(1)Compared with individuals without depression,those with depression showed greater right frontal EEG alpha asymmetry in the resting state.However,the pattern of frontal EEG alpha asymmetry in the resting state in depressive individuals seemed to disappear with age;(2)Compared with individuals without maternal depression,those with maternal depression showed greater right frontal EEG alpha asymmetry in the resting state,which indicated that genetic or experience-based influences have an impact on frontal EEG alpha asymmetry at rest;and(3)Frontal EEG alpha asymmetry in the resting state was stable,and little or no change occurred after antidepressant treatment.Finally,we concluded that the contrasting results may be due to differences in methodology,clinical characteristics,and participant characteristics.

Proposed Simple, Efficient Free Hand Technique for Frontal External Ventricular Drain (EVD) in Case of Small Ventricle: A Report of New Technique

Background: EVD is a common procedure done in neurosurgery and the residents should master it and this is what exactly means that it should be simple, safe, fast and accurate. EVD can be done through many entry points to the different part of the lateral ventricle but the famous site is the anterior horn of the lateral ventricle which is commonly approached through Kocher’s point which is a famous point for all neurosurgeon by its measurements of allocation. The commonest problem with EVD insertion into the anterior horn is the navigation of the ventricular cavity with the right trajectory and so the location of the catheter tip in the right place near the foramen of monro to ensure CSF draining. Size of the ventricle plays significant role in the success of the procedure especially free hand technique. The more dilated ventricle, the more chance to hit the ventricular cavity especially from the first trial and vice versa. In case of small ventricle, the procedure with free hand technique seems more complicated and the chance to hit the ventricle from the first trial may reduce especially with non-expert surgeon but may succeed in the following trials with increased risk of complications with more trials. Purpose: Most EVD’s are placed with freehand technique which depends on the operator skills to navigate the ventricle with right trajectory and hit the ventricle from the first trial, because many trials may complicate the procedure and produce undesirable side effects. So the key in this free hand technique is how to ensure the success from the first trial. In case of small anterior horn of the lateral ventricle, the procedure is even more difficult with the free hand technique and the classic Kocher point needs an expert to get the right trajectory to navigate such small ventricle. Our point idea came from this prospective and aimed at raising the success of the procedure especially in the first attempt with simple technique. Method: It is a new entry point for EVD insertion through frontal burr hole gained by the intersection of two lines: the first is running vertically from the ipsilateral medial canthus downward and the second is running horizontal along the coronal suture which is usually palpable as ridge on the scalp extended lateral from the bregma. Burr hole is done just anterior to this intersection and catheter is placed in a perpendicular trajectory toward the ventricular cavity. Result: It has been used in about (n = 50 cases) fulfilling the criteria of radiological small ventricle as defined and they were candidates for EVD insertion by free hand technique. Only 3 cases (6%) out of the 50 cases failed in the first attempt but succeeded in the following trial. So high rate of success in first trial is seen in the most of cases using this technique during a period of one year of our practice without significant side effects seen. Conclusion: Our study is not conclusive and needs further studies for more evaluation. It was a suggested point other than the classic Kocher point in case of free hand EVD insertion in small ventricle. We recommend to try it and report any advantages or disadvantages to the literature.

Forecast Error and Predictability for the Warm-sector and the Frontal Rainstorm in South China

In south China, warm-sector rainstorms are significantly different from the traditional frontal rainstorms due to complex mechanism, which brings great challenges to their forecast. In this study, based on ensemble forecasting, the high-resolution mesoscale numerical forecast model WRF was used to investigate the effect of initial errors on a warmsector rainstorm and a frontal rainstorm under the same circulation in south China, respectively. We analyzed the sensitivity of forecast errors to the initial errors and their evolution characteristics for the warm-sector and the frontal rainstorm. Additionally, the difference of the predictability was compared via adjusting the initial values of the GOOD member and the BAD member. Compared with the frontal rainstorm, the warm-sector rainstorm was more sensitive to initial error, which increased faster in the warm-sector. Furthermore, the magnitude of error in the warm-sector rainstorm was obviously larger than that of the frontal rainstorm, while the spatial scale of the error was smaller. Similarly, both types of the rainstorm were limited by practical predictability and inherent predictability, while the nonlinear increase characteristics occurred to be more distinct in the warm-sector rainstorm, resulting in the lower inherent predictability.The comparison between the warm-sector rainstorm and the frontal rainstorm revealed that the forecast field was closer to the real situation derived from more accurate initial errors, but only the increase rate in the frontal rainstorm was restrained evidently.

Recognition for Frontal Emergency Stops Dangerous Activity Using Nano IoT Sensor and Transfer Learning

Currently,it is difficult to extract the depth feature of the frontal emergency stops dangerous activity signal,which leads to a decline in the accuracy and efficiency of the frontal emergency stops the dangerous activ-ity.Therefore,a recognition for frontal emergency stops dangerous activity algorithm based on Nano Internet of Things Sensor(NIoTS)and transfer learning is proposed.First,the NIoTS is installed in the athlete’s leg muscles to collect activity signals.Second,the noise component in the activity signal is removed using the de-noising method based on mathematical morphology.Finally,the depth feature of the activity signal is extracted through the deep transfer learning model,and the Euclidean distance between the extracted feature and the depth feature of the frontal emergency stops dangerous activity signal is compared.If the European distance is small,it can be judged as the frontal emergency stops dangerous activity,and the frontal emergency stops dangerous activity recognition is realized.The results show that the average time delay of activity signal acquisition of the algorithm is low,the signal-to-noise ratio of the action signal is high,and the activity signal mean square error is low.The variance of the frontal emergency stops dangerous activity recognition does not exceed 0.5.The difference between the appearance time of the dangerous activity and the recognition time of the algorithm is 0.15 s,it can accurately and quickly recognize the frontal emergency stops the dangerous activity.

Comparison of Microphysical Characteristics of Warm-sector,Frontal and Shear-line Heavy Rainfall During the Pre-summer Rainy Season in South China

Warm-sector heavy rainfall(WR),shear-line heavy rainfall(SR),and frontal heavy rainfall(FR)are three types of rainfall that frequently occur during the pre-summer rainy season in south China.In this research,we investigated the differences in microphysical characteristics of heavy rainfall events during the period of 10-15 May 2022 based on the combined observations from 11 S-band polarimetric radars in south China.The conclusions are as follows:(1)WR has the highest radar echo top height,the strongest radar echo at all altitudes,the highest lightning density,and the most active ice-phase process,which suggests that the convection is the most vigorous in the WR,moderate in the FR,and the weakest in the SR.(2)Three types of rainfall are all marine-type precipitation,the massweighted mean diameter(Dm,mm)and the intercept parameter(Nw,mm^(-1) m^(-3))of the raindrops in the WR are the largest.(3)The WR possesses the highest proportion of graupel compared with the FR and SR,and stronger updrafts and more abundant water vapor supply may lead to larger raindrops during the melting and collision-coalescence processes.(4)Over all the heights,liquid and ice water content in the WR are higher than those in the SR and FR,the ratio of ice to liquid water content in the WR is as high as 27%when ZH exceeds 50 dBZ,definitely higher than that in the SR and FR,indicating that the active ice-phase process existing in the WR is conducive to the formation of heavy rainfall.

Comparison of Microphysical Characteristics Between Warm-sector and Frontal Heavy Rainfall in the South of China

During the April-June raining season,warm-sector heavy rainfall(WR) and frontal heavy rainfall(FR) often occur in the south of China,causing natural disasters.In this study,the microphysical characteristics of WR and FR events from 2016 to 2022 are analyzed by using 2-dimensional video disdrometer(2DVD) data in the south of China.The microphysical characteristics of WR and FR events are quite different.Compared with FR events,WR events have higher concentration of D<5.3 mm(especially D <1 mm),leading to higher rain rates.The mean values of Dmand lgNwof WR events are higher than that of FR events.The microphysical characteristics in different rain rate classes(C1:R~5-20 mm h-1,C2:R~20-50 mm h-1,C3:R~50-100 mm h^(-1),and C4:R> 100 mm h^(-1)) for WR and FR events are also different.Raindrops from C3 contribute the most to the precipitation of WR events,and raindrops from C2 contribute the most to the precipitation of FR events.For C2 and C3,compared with FR events,WR events have higher concentration of D <1 mm and D~3-4.5 mm.Moreover,the shape and slope(μ-A) relationships and the radar reflectivity and rain rate(Z-R) relationships of WR and FR events are quite different in each rain rate class.The investigation of the difference in microphysical characteristics between WR and FR events provide useful information for radar-based quantitative precipitation estimation and numerical prediction.

Role of Kuroshio frontal eddy in exchange between shelf water and Kuroshio water in East China Sea

Basic patterns of the reversal of the Kuroshio water toward the shelf, intrusion of the shelf mixed waterinto the Kuroshio and uplifting of the near-bottom nutrient-rich water into the upper layer by the pumping of the frontal eddy are analyzed on the basis of satellite infrared images and hydrologic, chemical and biological observations. Results show that the Kuroshio frontal eddies play a very important role in the exchange between the shelf water and the Kuroshio water. The estimation of the average volume transports for three frontal eddy events indicates that the shelf mixed water entrained by an eddy into Kuroshio is 0.44×10~6 m3/s and the reversal Kuroshio water onto the shelf region only 0.04×10~6 m3/s. Along the whole shelf edge, the volume transport of the shelf mixed water entrained by the eddies into the Kuroshio is 1.8×10~6 m3/s. The nutrient (NO3-N) flux pumped to the euphotic zone and input to the continental shelf through a column with 1 m wide is 974 μmol/(s·m) when there is frontal eddy and only 79 μmol/(s·m) in the case of no frontal eddy. Yearly nutrient (NO3-N) flux input to the shelf area caused by the frontal eddy is 1.7×10~5 t/a.

Analysis of the CHRNA7 gene mutation and polymorphism in Southern Han Chinese patients with nocturnal frontal epilepsy

Objective:To detect the CHRNA7 gene mutation and polymorphism in Southern Han Chinese patients with nocturnal frontal lobe epilepsy(NFLE).Methods:Blood samples were collected from 215 Southern Han Chinese patients with NFLE and 200 healthy Southern Han Chinese control subjects.Genomic DNA was extracted,and CHRNA7 whole genome exons were amplified by the polymerase chain reaction and subjected to Sanger sequencing.Results:No CHRNA7 gene mutation was detected in all of the NFLE patients.However,five single nucleotide polymorphisms(SNPs)in sporadic cases were found,located in exons 5,6.and 7 of the CHRNA7 gene.Among them,c.690G>A and c.698A>G are known SNPs,while c.370G>A,c.654C>T,and c.497-498delTG were newly discovered SNPs.These SNPs were also found in some of the healthy controls.Conclusions:No CHRNA7 gene mutation was identified in Southern Han Chinese patients with NFLE.The CHRNA7 gene is probably not responsible for NFLE in this population.

Obese Adolescents with Type 2 Diabetes Mellitus Have Hippocampal and Frontal Lobe Volume Reductions

The rates of type 2 diabetes (T2DM) continue to parallel the rising rates of obesity in the United States, increasingly affecting adolescents as well as adults. Hippocampal and frontal lobe reductions have been found in older adults with type 2 diabetes, and we sought to ascertain if these brain alterations were also present in obese adolescents with T2DM. In a cross-sectional study we compared MRI-based regional brain volumes of 18 obese adolescents with T2DM and 18 obese controls without evidence of marked insulin resistance. Groups were matched on age, sex, school grade, ethnicity, socioeconomic status, body mass index, and waist circumference. Relative to obese controls, adolescents with T2DM had significantly reduced hippocampal and prefrontal volumes, and higher rates of global cerebral atrophy. Hemoglo-bin A1c, an index of long-term glycemic control, was inversely associated with prefrontal volume and positively associ-ated with global cerebral atrophy (both p < 0.05). Brain integrity is negatively impacted by T2DM already during ado-lescence, long before the onset of overt macrovascular disease. Paralleling the findings of greater vascular and renal complications among obese adolescents with severe insulin resistance and T2DM relative to their age-matched peers with type 1 diabetes, we find clear evidence of possible brain complications. Our findings call for aggressive and early intervention to limit the negative impact of obesity-associated insulin resistance leading to T2DM on the developing brains of adolescents.

Synchronization between frontal eye field and area V4 during free-gaze visual search

Information flow between the prefrontal and visual cortices is critical for visual behaviors such as visual search. To investigate its mechanisms, we simultaneously recorded spike and local field potential (LFP) signals in the frontal eye field (FEF) and area V4 while monkeys performed a free-gaze visual search task. During free-gaze search, spike-LFP coherence between FEF and V4 was enhanced in the theta rhythm (4–8 Hz) but suppressed in the alpha rhythm (8–13 Hz). Cross-frequency couplings during the Cue period before the search phase were related to monkey performance, with higher FEF theta-V4 gamma coupling and lower FEF alpha-V4 gamma coupling associated with faster search. Finally, feature-based attention during search enhanced spike-LFP coherence between FEF and V4 in the gamma and beta rhythms, whereas overt spatial attention reduced coherence at frequencies up to 30 Hz. These results suggest that oscillatory coupling may play an important role in mediating interactions between the prefrontal and visual cortices during visual search.

Integrative Monsoon Frontal Rainfall Experiment(IMFRE-I):A Mid-Term Review

The mei-yu season,typically occurring from mid-June to mid-July,on average,contributes to 32%of the annual precipitation over the Yangtze-Huai River Valley(YHRV)and represents one of the three heavy-rainfall periods in China.Here,we briefly review the large-scale background,synoptic pattern,moisture transport,and cloud and precipitation characteristics of the mei-yu frontal systems in the context of the ongoing Integrative Monsoon Frontal Rainfall Experiment(IMFRE)field campaign.Phase one of the campaign,IMFRE-I,was conducted from 10 June to 10 July 2018 in the middle reaches of the YHRV.Led by the Wuhan Institute of Heavy Rain(IHR)with primary support from the National Natural Science Foundation of China,IMFRE-I maximizes the use of our observational capacity enabled by a suite of ground-based and remote sensing instruments,most notably the IHR Mesoscale Heavy Rainfall Observing System(MHROS),including different wavelengths of radars,microwave radiometers,and disdrometers.The KA350(Shanxi King-Air)aircraft participating in the campaign is equipped with Ka-band cloud radar and different probes.The comprehensive datasets from both the MHROS and aircraft instruments are combined with available satellite observations and model simulations to answer the three scientific questions of IMFRE-I.Some highlights from a previously published special issue are included in this review,and we also briefly introduce the IMFRE-II field campaign,conducted during June-July 2020,where the focus was on the spatiotemporal evolutions of the mei-yu frontal systems over the middle and lower reaches of the YHRV.

Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)over the Middle and Lower Reaches of the Yangtze River in 2020

Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)was conducted over the middle and lower reaches of the Yangtze River during the period 16 June to 19 July 2020.This paper provides a brief overview of the IMFRE-II field campaign,including the multiple ground-based remote sensors,aircraft probes,and their corresponding measurements during the 2020 mei-yu period,as well as how to use these numerous datasets to answer scientific questions.The highlights of IMFRE-II are:(1)to the best of our knowledge,IMFRE-II is the first field campaign in China to use ground-based,airborne,and spaceborne platforms to conduct comprehensive observations over the middle and lower reaches of the Yangtze River;and(2)seven aircraft flights were successfully carried out,and the spectra of ice particles,cloud droplets,and raindrops at different altitudes were obtained.These in-situ measurements will provide a“cloud truth”to validate the ground-based and satellite-retrieved cloud and precipitation properties and quantitatively estimate their retrieval uncertainties.They are also crucial for the development of a warm(and/or cold)rain conceptual model in order to better understand the cloud-to-rain conversion and accretion processes in mei-yu precipitation events.Through an integrative analysis of ground-based,aircraft,and satellite observations and model simulations,we can significantly improve our cloud and precipitation retrieval algorithms,investigate the microphysical properties of cloud and precipitation,understand in-depth the formation and dissipation mechanisms of mei-yu frontal systems,and improve cloud microphysics parameterization schemes and model simulations.

SYNTHESIS OF MACROPOROUS POLYACRYLAMIDE AND POLY(NISOPROPYLACRYLAMIDE) MONOLITHS VIA FRONTAL POLYMERIZATION AND INVESTIGATION OF PORE STRUCTURE VARIATION OF MONOLITHS

A novelty method,frontal polymerization(FP),was employed to directly produce a series of polyacrylamide (PAM),poly(N-isopropylacrylamide)(PNIPAM) and acrylamide-N-isopropylacrylamide copolymer macroporous monoliths. Field emission scanning electronic microscope and mercury intrusion method were adopted to measure some parameters of these monoliths,such as frame,pore size distribution as well as porosity.Effects of types of monomer,thicker and surfactant on porous structure of monoliths were studied.A var...

The Theory Study of the Influence of the Topography on the Cold Frontal Motion

In order to study the characteristics of cold frontal motion over the arbitrary topography, the velocity of cold frontal movement is derived by using the one layer shallow-water model. The results show that there exist the retardation in upwind side and rapid descent in the lee slope when the cold front crosses the topography.

Energy Paths that Sustain the Warm-Sector Torrential Rainfall over South China and Their Contrasts to the Frontal Rainfall: A Case Study

Predicting warm-sector torrential rainfall over South China,which is famous for its destructive power,is one of the most challenging issues of the current numerical forecast field.Insufficient understanding of the key mechanisms underlying this type of event is the root cause.Since understanding the energetics is crucial to understanding the evolutions of various types of weather systems,a general methodology for investigating energetics of torrential rainfall is provided in this study.By applying this methodology to a persistent torrential rainfall event which had concurrent frontal and warm-sector precipitation,the first physical image on the energetics of the warm-sector torrential rainfall is established.This clarifies the energy sources for producing the warm-sector rainfall during this event.For the first time,fundamental similarities and differences between the warm-sector and frontal torrential rainfall are shown in terms of energetics.It is found that these two types of rainfall mainly differed from each other in the lower-tropospheric dynamical features,and their key differences lay in energy sources.Scale interactions(mainly through downscale energy cascade and transport)were a dominant factor for the warm-sector torrential rainfall during this event,whereas,for the frontal torrential rainfall,they were only of secondary importance.Three typical signals in the background environment are found to have supplied energy to the warm-sector torrential rainfall,with the quasi-biweekly oscillation having contributed the most.

A Motor Programming Task Activates the Prefrontal Cortex More than a Sensitivity-to-Interference Task or an Inhibitory Control Task in Older Adults

The objectives of this study were to detect age-related differences in activation of the prefrontal cortex (PFC) during the tasks of hand motions and to determine an activity-related task type activating the PFC. PFC activation during three tasks, three subtests of the Frontal Assessment Battery (FAB), was investigated in 77 healthy adults by using near-infrared spectroscopy (NIRS). The tasks were a motor programming task (FAB 3), a sensitivity-to-interference task (FAB 4) and an inhibitory control task (FAB 5). We divided participants into three age groups of Younger (20 - 39 years), Middle-aged (40 - 59 years), and Older (60 - 81 years), and compared relative changes in oxygenated hemoglobin concentration in the PFC during the tasks. The activation in the frontal pole (FP) and the dorsolateral prefrontal cortex (DLPFC) during a motor programming task and a sensitivity-to-interference task showed no main effects by age. The results indicated that they were not likely to be affected by age-related cognitive decline compared to an inhibitory control task. In addition, in the Older group, a motor programming task induced significantly greater activation than a sensitivi-ty-to-interference task at eleven channels out of twelve on which we focused (p < 0.05). It was suggested that some characteristic factors included in the motor programming task such as repetition of a series of hand motions and attention to action have the potential to contribute to PFC activation in older adults. These findings provide a clue to understanding daily activities available to suppress cognitive decline of older adults by activating the PFC.

Unilateral Bone Window Cerebral Falx Incision of Bilateral Frontal Lobes Cerebral Contusion and Laceration under Neuroendoscopy and Literature Review

Background: Bilateral frontal lobes cerebral contusion and laceration is one unique brain injury in neurosurgery department. It is characteristic of recessive attacking and develops quickly. The unilateral cerebral falx incision is a new minimally invasive surgery that can solve bilateral frontal lobes cerebral contusion and laceration in one surgery. However, it has some limitations in removal of contralateral frontal hematoma and hemostasis due to the limited field of view under the microscope. The unilateral bone window cerebral falx incision of bilateral frontal lobes cerebral contusion and laceration under a neuroendoscopy can acquire a good illumination and field of view. This is beneficial to complete removal of contralateral hematoma, effective hemostasis and retaining brain tissue functions to the maximum extent. Case Presentation: The patient, a 55-year-old man, was hospitalized for “consciousness disorder by 12 h because of car accident”. Physical Examination: Coma, GCS score of E1V2M5, bilateral pupil diameter of 2 mm, presence of light response, contusion of scalp at the left top, peripheral dysphoria and bilateral Bartter syndrome negative. The patient has a history of non-traumatic cerebral stroke 3 years ago. Head CT: Longitudinal fracture of frontal parietal occipital bone, bilateral frontal lobes contusion and laceration, subarachnoid hemorrhage. Diagnosis: Bilateral frontal lobes contusion and laceration, longitudinal fracture of frontal parietal occipital bone, subarachnoid hemorrhage and hematoma of scalp. In emergency treatment, unilateral bone window cerebral falx incision of bilateral frontal lobes cerebral contusion and laceration under a neuroendoscopy was performed. The surgery has achieved satisfying effect. Discussion: This case realized the goal of removing contralateral frontal hematoma through unilateral craniotomy under a neuroendoscopy. Due to the clear field of view, it retained extracerebral layer structures of contralateral olfactory nerve protection frontotemporal completely. Moreover, this surgical technique is conducive to intraoperative recognition of pericallosal arteries and lateral fractured blood vessels. It also involves protection, which conforms to the minimally invasive philosophy. The proposed surgical technology can eliminate contralateral frontal hematoma under a good field of view. However, it is suggested not to manage with the further operation on patients who have brain swelling and difficulties in exposure of cerebral falx. These patients need to determine causes of brain swelling and choose bilateral craniectomy if necessary. Conclusions: Unilateral bone window cerebral falx incision of bilateral frontal lobes cerebral contusion and laceration under a neuroendoscopy is a new application of minimally invasive philosophy in craniocerebral injury operation. It still needs further clinical verifications and experience accumulation.

GEOLOGY OF THE TAPLEJUNG WINDOW AND FRONTAL BELT, FAR EASTERN NEPAL HIMALAYA

We present a preliminary result of the study carried out in the northern and southern sections of the Taplejung Window and the frontal part of the thrust sheet near The study area comprises of three tectonic units: (1) The Lesser Himalayan (LH) Unit exposed in the Taplejung Window (Fig. 1a, 1b, Upreti and Le Fort, 1999), (2) The thrust sheet consisting of the Higher Himalayan Crystallines (HHC) and forming the hanging wall of the Main Central Thrust (MCT) exposed around the window, and which has traveled far south reaching very close to the MBT (Fig.1c), and (3) The Lesser Himalayan Unit sandwiched between the MBT and the southern extension of the MCT (Fig.1c).The LH Unit of the window and the sandwiched southern part consist mainly of phyllites, schists, quartzites, gneisses and augen gneiss of granitic origin with minor association of amphibolites, marbles (Fig. 1a, 1c). An foliated granitic rock is found within the phyllites and schists near the Kabeli bridge within the window. The HHC consists mainly of the garnet, kyanite, sillimanite bearing banded gneisses interbedded with quartzites with incipient traces of mobilization. Detailed petrography of all these rocks are described.

Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice

Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall(SFR) during early summer(May-June mean, MJ) by considering Arctic sea ice(ASI) variability as a new potential predictor. A MJ SFR index(SFRI), the leading principle component of the empirical orthogonal function(EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations(1979-2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure(SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979-2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models’ ensemble prediction for the 1979-2010 period(0.72 versus 0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall.